WO2021013678A1

WO2021013678A1 - Deep drilling machine

Info

Publication number: WO2021013678A1
Application number: PCT/EP2020/070107
Authority: WO
Inventors: Jan WOLF; Jochen Buck; Matthias GÖTZ
Original assignee: Tbt Tiefbohrtechnik Gmbh + Co
Priority date: 2019-07-23
Filing date: 2020-07-16
Publication date: 2021-01-28

Abstract

The invention relates to a deep drilling machine (100) comprising a machine bed (102) which supports a linear guide system (104), a tool spindle unit (110) which can travel linearly on the linear guide system (104) and has at least one tool spindle (112) which is rotatable about a spindle axis (115) by means of a spindle drive (114) and has a tool receptacle (116) for receiving a drilling tool, a counter-holding unit (120), which has, on a side facing the tool spindle unit (110), a workpiece receptacle (126) for receiving a first end portion of a workpiece (W), and a workpiece receptacle unit (130) which is arranged between the tool spindle unit (110) and the counter-holding unit (120) and has, on the side facing the counter-holding unit (120), a workpiece receptacle (136) for receiving the second end portion of the workpiece (W) opposite the first end portion, and a passage opening for guiding the drilling tool through. According to the invention, there is a workpiece sliding unit (200) which is arranged between the counter-holding unit (120) and the workpiece receptacle unit (130) and has a transverse slide (210) which is movable back and forth by means of a displacement drive in a displacement direction (215) extending perpendicularly to the spindle axis (115). The transverse slide (210) has, for each tool spindle, a first workpiece pre-centering device and a second workpiece pre-centering device parallel thereto, which are movable back and forth between a first and at least one second position (P2) by displacing the transverse slide (210) parallel to the displacement direction (215). The workpiece pre-centering devices are designed such that a workpiece (150) carried by a workpiece pre-centering device is oriented relative to the spindle axis (115) so as to be substantially ready for drilling when the workpiece pre-centering device is in the first position, and is arranged adjacent to the spindle axis (115) so as to be freely accessible for a loading operation when the workpiece pre-centering device is in the second position.

Description

Deep drilling machine

AREA OF APPLICATION AND STATE OF THE ART

The invention relates to a deep drilling machine according to the preamble of claim 1.

Deep drilling - also known as deep hole drilling - is a special drilling method that is used primarily to produce holes with a diameter of 0.5 mm to 1,500 mm at a depth of more than three times the diameter. By means of deep drilling, very deep holes with a depth / diameter ratio greater than 200 can be produced.

A continuous supply of coolant under pressure and a steady chip evacuation without chip removal is characteristic of deep drilling. This means that even deep bores can be made in one pass using the deep drilling method, and the drill does not have to be removed from the bore in between to remove the chips. Another characteristic of deep drilling is that deep drilling tools guide themselves in the bore in order to avoid the bore running out of the intended direction of the bore axis.

There are essentially three deep drilling methods, namely single-lip deep drilling (ELB deep drilling), BTA deep drilling, which is also known as STS ("Single Tube System"), and ejector deep drilling, which is also known as deep drilling Two-pipe system is known. These methods differ in the deep drilling tools used, in the coolant flow and in the flow of chips.

A deep hole drilling machine is a machine tool specially designed for deep hole drilling. A generic deep drilling machine has a machine bed which carries a linear guide system. With a horizontal deep drilling machine, this is aligned horizontally. A tool spindle unit is guided in a linearly movable manner on the linear guide system. The tool spindle unit has at least one tool spindle which can be rotated about a spindle axis by means of a spindle drive and has a tool holder for receiving a drilling tool (eg deep drilling tool, pilot drill, twist drill, countersink). Furthermore, a counter-holding unit is provided which, on a side facing the tool spindle unit, has a workpiece holder for receiving a first end section of a workpiece. There is also one between the tool spindle unit and the Counterholding unit arranged workpiece receiving unit arranged, which has on the side facing the counterholding unit a workpiece holder for receiving the second end section of the workpiece opposite the first end section, as well as a feed-through opening for passing the drilling tool through.

A workpiece is thus received in the workpiece receptacles at two opposite end sections. In the ready-to-operate clamped state, the workpiece is arranged in such a way that the intended bore axis runs coaxially to the spindle axis. The spindle axis can be coaxial to the workpiece axis or offset parallel to it. When drilling, the drilling tool is then advanced on the linear guide system by the controlled advance of the tool spindle unit and creates the hole in the workpiece clamped on both sides.

It is often desirable to increase productivity through the use of automation equipment for changing workpieces and / or tools. Automation devices for deep hole drilling machines are known, for example, for the transport of workpieces for linking in automatically operating production lines or for decoupling deep hole drilling machines from the presence of the operating staff. If automatic workpiece change is required for series production, deep drilling machines are nowadays often equipped with automation devices in the form of indexing belts. The workpieces to be drilled are placed on the indexing belt in front of the deep drilling machine and the drilled finished parts are removed from the rear of the machine. The machine is decoupled from the operator's presence through the storage function of the indexing belt, so that, for example, multiple machine operation is possible. This also enables the machine to be integrated into a production line, with the loading equipment being able to be supplemented with translators for linking with upstream or downstream machines or systems (see e.g. KJ. Conrad (ed.) "Taschenbuch der Werkzeugmaschinen", Fachbuchverlag Leipzig) , 3rd edition (2015) pages 504, 505).

TASK AND SOLUTION

It is an object of the invention to provide a deep drilling machine of the type mentioned at the outset which enables a quick workpiece change so that the non-productive times that cannot be used for drilling can be reduced. To achieve this object, the invention provides a deep drilling machine with the features of claim 1. Advantageous further developments are given in the dependent claims. The wording of all claims is incorporated into the content of the description by reference.

According to one formulation of the invention, a workpiece displacement unit is provided on the deep hole drilling machine, which is arranged between the counter-holding unit and the workpiece receiving unit. The integrated workpiece displacement unit comprises a cross slide which can be moved back and forth by means of a displacement drive in a displacement direction running perpendicular to the spindle axis. The cross slide has a first workpiece pre-centering device and a second workpiece pre-centering device parallel thereto, which can be moved back and forth between a first position and at least one second position by moving the cross slide parallel to the direction of displacement. The two workpiece pre-centering devices are assigned to the spindle axis and are intended for the "operation" of this spindle axis. Each of the workpiece pre-centering devices is designed in such a way that a workpiece carried by a workpiece pre-centering device is aligned essentially ready for drilling to the assigned spindle axis when the workpiece pre-centering device is in the first position and that the workpiece pre-centering device is arranged next to the spindle axis when the workpiece pre-centering device is in the second position.

Since the workpiece can be clamped in the first position, the first position can also be referred to as the clamping position. The second position is characterized in that the workpiece pre-centering device is accessible for a loading operation in the second position. Therefore, the second position can also be referred to as the loading position. There are embodiments in which a workpiece precentering device which is located in the first position can also be loaded or unloaded there.

A workpiece pre-centering device enables the workpiece picked up by it to be pre-centered in relation to the spindle axis. This means that the pre-centered workpiece is largely correctly aligned to the spindle axis, with exact positioning, as required for drilling, not being required and usually not being achieved. While the intended borehole axis must be aligned coaxially to the spindle axis in the correct position for drilling, a pre-centered workpiece may still have a slight axial offset. The “correct” position of the workpiece required for the drilling operation is then achieved by the workpiece is clamped between the associated workpiece holders of the counter-holding unit on the one hand and the workpiece holder unit on the other hand. The workpiece holders can automatically take over and center the pre-centered workpiece by moving the counter holding unit and workpiece holder unit together.

The linear translatory movement of the workpiece displacement unit parallel to the direction of displacement enables a direct transfer of a picked-up workpiece between a second position outside the spindle axis and the first position (clamping position) by moving the cross slide linearly. Further translational movements in other directions, as are provided for example in step-stroke transport devices, are not required and are not provided. It can therefore be a pure displacement system. Apart from the linear mobility in the direction of displacement, the cross slide does not require any further degrees of freedom in directions perpendicular thereto, so that in this respect a structurally simple and easily automatable solution results. When the workpiece pre-centering device is in the second position (loading position), it is accessible for manual or machine loading and unloading. Because at least two workpiece pre-centering devices are assigned to a spindle axis, loading and unloading parallel to production is possible, i.e. loading or unloading that is carried out at least in phases at the same time as a drilling operation is in progress. As a result, the non-productive times for deep drilling that cannot be used for drilling can be reduced compared to conventional solutions.

Depending on the deep drilling process, different types of counter holding unit and workpiece holding unit are possible. The counter-holding unit can, for example, have a tailstock which is arranged coaxially to the spindle axis and has a conical clamping receptacle which engages in a centering bore introduced into the end of the workpiece or on an outer bevel. It is also possible that the counter-holding unit has a rotatable workpiece spindle for each tool spindle, which can be driven passively rotatably or rotatably with the aid of its own spindle drive. The workpiece spindle can be arranged and driven coaxially to the tool spindle, for example in order to move the workpiece during the deep drilling operation in a direction of rotation opposite to that of the deep drilling tool. The axis of rotation of the workpiece spindle can also be offset parallel to the tool spindle axis, for example for positioning from one hole to the next when producing several holes that lie on a pitch circle. There are also different design options for the workpiece holding unit. In many embodiments, the workpiece receiving unit has a drill bushing carrier which can be used, for example, in combination with single-lip deep drilling tools. Sometimes a drilling oil supply apparatus or a tool passage opening is provided instead of a drill bushing carrier.

(At least) two workpiece pre-centering devices arranged parallel to one another and offset in relation to one another are assigned to a spindle axis. With an appropriate design of the cross travel of the cross slide, it can be achieved that, in addition to each spindle axis, there is a loading position on two opposite sides of the spindle axis in the travel direction. Two second positions (loading positions) can thus be created on opposite sides of the spindle axis for each spindle axis, which can be used alternately with one another. This enables efficient loading and unloading with only short transverse stroke movements of the cross slide. The loading and unloading processes can be carried out at the same time or overlapping in time with the drilling operation, i.e. parallel to the main time.

The deep drilling machine can be a single-spindle deep drilling machine (with only a single tool spindle) or a multi-spindle deep drilling machine. Some embodiment is characterized in that the tool spindle unit has at least two tool spindles which can be rotated about mutually parallel spindle axes which are spaced apart from each other in a spindle plane. The spindle plane is preferably horizontal, so that it is a horizontal deep drilling machine. The counter-holding unit then has a workpiece holder for each tool spindle and the workpiece holder unit has a workpiece holder for each tool spindle as well as a feed-through opening for passing a drilling tool through. In these embodiments, the cross slide can be moved back and forth parallel to the spindle plane by means of the displacement drive and has a first workpiece pre-centering device for each of the tool spindles and a second workpiece pre-centering device parallel to it, each of which is set between a first by moving the cross slide in the direction of displacement Position and at least a second position can be moved back and forth. By increasing the number of tool spindles that can be operated in parallel, the productivity of the deep drilling machine can be increased.

More than two tool spindles can be provided, for example three or four. More than two tool spindles can be useful, for example, if you want to increase productivity with manual loading. The tool spindle unit preferably has exactly two tool spindles, as a result of which a considerable increase in productivity is possible with limited additional expenditure in the construction. The number of workpiece pre-centering devices is preferably twice as large as the number of Tool spindles, so that in preferred embodiments the workpiece displacement unit has exactly four workpiece precentering devices that are parallel to one another.

In the case of a multi-spindle deep hole drilling machine, the construction is preferably chosen so that a transverse stroke path of the cross slide is smaller than the spindle distance between adjacent spindle axes, so that for each of the spindle axes a second position (i.e. a loading position suitable for loading) lies in an intermediate area between the spindle axes. In the case of a multi-spindle deep hole drilling machine, a quick workpiece change can thus be achieved with the aid of a single required linear movement of the cross slide in connection with direct loading and unloading at an intermediate location between the spindle axes.

According to a further development, the counter-holding unit has a workpiece spindle for each tool spindle which can be rotated axially parallel to it and to which the workpiece holder is attached. The axis of rotation of the workpiece spindle can be arranged coaxially to the spindle axis (axis of rotation of the tool spindle) or offset parallel to it. The workpiece spindle is preferably assigned its own spindle drive for active rotation of the workpiece spindle. With a coaxial arrangement of the tool spindle and workpiece spindle, the workpiece can be actively rotated during the deep drilling operation with the aid of this spindle drive, possibly in opposite directions to the rotation of the deep drilling tool and / or at a different rotational speed. In the case of a parallel offset arrangement, the active rotation of the workpiece spindle can be used, for example, to gradually position holes in a workpiece that are on a pitch circle for machining coaxially to the spindle axis of the tool spindle.

According to a further development, the workpiece pre-centering devices are adjustable with regard to their position on the cross slide. For example, a stepless height adjustment of the workpiece pre-centering devices can be provided. This enables the workpiece displacement device to be easily adapted to accommodate workpieces of different dimensions.

Some embodiments are characterized in that a workpiece pre-centering device has two receiving structures which are arranged axially offset to one another and each have two bearing surfaces aligned at an angle to one another such that the receiving structures widen upwards. In particular, prismatically designed receiving structures can be provided, for example with a V-shape opening upwards. This enables stable reception of, for example, rotationally symmetrical workpieces of different diameters. These then rest on linear contact points on the inclined support surfaces. Because there is an axial distance between the receiving structures, the space between the receiving structures can be used by a workpiece pre-centering device to accommodate other elements, for example to accommodate the displacement drive. The receiving structures can be set separately from one another.

The workpiece displacement unit can be mounted in a fixed position on the machine bed. In preferred embodiments, however, it is provided that the workpiece displacement unit has a base slide which can be moved linearly on the linear guide system, the base slide carrying the cross slide. With the help of the basic slide, the axial position of the workpiece displacement unit can be continuously adjusted so that the workpiece displacement unit can be optimally positioned for workpieces of different lengths, for example.

In some embodiments, the cross slide and the workpiece pre-centering devices form components of an interchangeable unit, which is attached to the basic slide as a complete assembly and can be exchanged. This makes it easy to convert the deep hole drilling machine to other workpiece types or other workpiece dimensions.

Preferred embodiments are characterized in that the cross slide has at least one workpiece steady rest for each of the workpiece pre-centering devices, with each of the workpiece pre-centering devices preferably being assigned two workpiece steady rest arranged axially offset from one another. With the help of a workpiece steady rest, a workpiece clamped on both sides can be supported at at least one point in the area between its end sections, so that a bending of the workpiece and thus drilling errors can be effectively prevented. Equipping with one or more workpiece steady rests can be particularly advantageous when deep drilling relatively long and / or relatively thin workpieces. The workpiece displacement unit thereby has a double function, since on the one hand a quick workpiece change is supported and on the other hand reliable workpiece support is provided during drilling operation.

The workpiece steadies can be designed as self-centering workpiece steadies, in particular with support rollers, so that the workpiece can rotate during the drilling operation. A workpiece steady rest can preferably be switched automatically between an open configuration and a closed configuration, with In the open configuration, a workpiece can be inserted into the workpiece pre-centering device or removed from it, while the steady rest takes over the workpiece during the transition from the open configuration to the closed configuration and supports it in a position centered on the spindle axis.

The use of a workpiece displacement unit on a deep drilling machine of the type dealt with here can considerably simplify and accelerate the change of workpiece, both for manual loading and unloading and for automated loading and unloading. Some embodiments are characterized by an automatic loading device assigned to the deep drilling machine for the automated loading and unloading of workpiece pre-centering devices located in a loading position. The charging device can for example comprise a robot unit, in particular in the form of an articulated arm robot. The charging device can be integrated with the deep drilling machine in such a way that the charging device is controlled on the basis of control signals from a control unit of the deep drilling machine. As a result, the working movements of the loading device and the workpiece displacement device can be coordinated via the control unit of the deep drilling machine or, alternatively, by exchanging signals between the controls of the deep drilling machine and the loading device.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and aspects of the invention emerge from the claims and from the following description of preferred exemplary embodiments of the invention, which are explained below with reference to the figures.

1 shows an oblique perspective partial view of a deep drilling machine according to an embodiment of the invention;

Fig. 2 shows an oblique perspective view of a workpiece displacement unit for

Use on a two-spindle deep drilling machine;

Fig. 3 shows in FIGS. 3A to 3H different steps in working movements of a

Workpiece displacement unit on a two-spindle deep drilling machine according to an exemplary embodiment; and Fig. 4 shows an oblique perspective view of another embodiment of a

Workpiece displacement unit for use with a two-spindle deep drilling machine.

DETAILED DESCRIPTION OF THE EMBODIMENTS

1 shows an oblique perspective partial view of a deep drilling machine 100 according to an exemplary embodiment. The deep drilling machine 100 is designed as a two-spindle horizontal deep drilling machine. The deep drilling machine 100 has a machine bed 102 which is several times longer in the longitudinal direction (z-direction of the machine coordinate system MKS) than in the transverse direction running perpendicular thereto (x-direction of the machine coordinate system). A linear guide system 104 with two guide rails 104-1, 104-2 parallel to one another is attached to the top of the machine bed. The linear guide system carries a tool spindle unit 110, which can be moved in a controlled manner on the linear guide system in the longitudinal direction of the deep drilling machine with the aid of an electromechanical drive. The tool spindle unit 110 has exactly two tool spindles, namely a first tool spindle 112-1, which is closer to the operating side shown, and a second tool spindle 112-2, each of which has its own spindle drive 113-1, 113-2 around its respective spindle axis (first spindle axis 115-1 or second spindle axis 115-2) are rotatable. The horizontally running spindle axes lie in a common, horizontal spindle plane 118 at a spindle distance 117 from one another. Each of the tool spindles has at its free end a tool holder 116-1, 116-2 for holding a deep drilling tool.

The deep hole drilling machine is designed to receive the workpieces to be drilled at two opposite end sections in such a way that the sections of the workpieces to be provided with a deep hole bore are coaxial with the spindle axes. For this purpose, a workpiece receiving unit 130 in the form of a drill bushing carrier 130 is provided at a distance in front of the tool spindle unit and a counter-holding unit 120 is provided further away from the tool spindle unit 110. The drill bushing carrier 130 is firmly mounted on the machine bed. The counter-holding unit 120 is mounted on a slide that can be moved linearly on the linear guide system 104, so that the distance between the workpiece receiving unit 130 and the counter-holding unit 120 is continuously adjustable. This means that the deep hole drilling machine can be easily adapted to different workpiece dimensions and tool types. The counter-holding unit 120 has a workpiece spindle 122-1, 122-2 for each of the tool spindles 112-1, 112-2, which is rotatably mounted within a headstock coaxially to the associated spindle axis. Each of the workpiece spindles can be rotated around its spindle axis with the aid of its own spindle drive 123-1, 123-2, the spindle drives being controllable with regard to the rotational speed and direction of rotation and position. Each of the workpiece spindles has a workpiece holder 126-1 or 126-2 on the side facing the tool spindle unit 110, each of which is intended to receive and clamp a first end section of a workpiece W remote from the tool.

The workpiece receiving unit 130 or the drill bushing carrier 130 also has a separate workpiece receiving element 136-1, 136-2 on the side facing the counter-holding unit 120 for each of the tool spindles, each of which is designed to receive the second end section of the workpiece opposite the first end section and near the tool . The workpiece receiving unit 130 furthermore has a feed-through opening for each of the spindle axes for passing the drilling tool received on the tool spindle. Since the structure and function of drill bushing supports or similar devices, such as drilling oil supply apparatus, are known to the person skilled in the art, a more detailed description is dispensed with here.

The deep drilling machine 100 is equipped with devices for a partially or fully automated workpiece change. An essential component of the automation devices is a workpiece displacement unit 200, which is integrated into the deep drilling machine and is arranged between the counter holding unit 120 and the workpiece receiving unit 130. Structural details and the mode of operation of the workpiece displacement unit 200 are explained in greater detail in connection with FIGS. 1, 2 and 3, among other things. Fig. 4 shows an alternative embodiment of a workpiece displacement unit.

The workpiece displacement unit 200 has a base slide 202, which has slide shoes on its underside that run on the guide rails of the linear guide system 104 so that the base slide can be moved on the linear guide system in the longitudinal direction of the machine coordinate system (z-direction). On its upper side, the base slide 202 carries a cross slide 210 which can be moved back and forth on correspondingly aligned horizontal guide rails in a horizontal displacement direction 215 running perpendicular to the spindle axes 115-1, 115-2. A displacement drive 212 integrated in the workpiece displacement unit 200 is provided to generate this pendulum movement or to and fro movement. This has one lying horizontally hydraulically operated cylinder 213, which is permanently mounted on the cross slide. A piston moves in the cylinder 213, to which an outwardly guided piston rod 214 is attached, the free end of which is attached to a bearing element 203 fixedly connected to the base slide 202. With the aid of the shift drive, the cross slide can be moved back and forth between two defined end positions via a cross stroke 217

The cross slide 210 has a horizontal slide plate 230, which carries on its upper side two transversely elongated, vertically standing frame elements 232-1, 232-2, which are spaced apart in the longitudinal direction (z-direction) and by several longitudinal connecting ribs 233 are connected to each other, so that a stable frame structure results. The displacement drive 212 is arranged in the installation space between the two frame elements 232-1, 232-2.

The cross slide 210 has a total of four workpiece precentering devices, namely two workpiece precentering devices lying parallel to one another for each of the two tool spindles, namely a first workpiece precentering device 220-1 and a second workpiece precentering device 220-2 parallel thereto. Each of the workpiece precentering devices can be moved back and forth between two positions with different functions, namely between a clamping position and at least one loading position, by moving the cross slide 210 in the direction of displacement 215 by the cross stroke path 217. When a workpiece pre-centering device is in the clamping position, a workpiece carried by the workpiece pre-centering device is aligned essentially ready for drilling with the assigned spindle axis. This means that the area in which the bore axis of the bore to be generated later lies is already in the vicinity of the spindle axis, an exactly coaxial alignment being possible but not necessary. The term “pre-centering” expresses that centering should already be approximately given, but exact centering is not yet required. If, on the other hand, the workpiece pre-centering device is in a loading position, it is located next to the assigned spindle axis in such a way that the workpiece pre-centering device, when empty, can be loaded with a workpiece (blank) that has not yet been processed or, if the Workpiece pre-centering device carries an already drilled workpiece (finished part), this can be removed from or unloaded from the workpiece pre-centering device. In the case of fully automated deep hole drilling machines, these loading and unloading processes can in any case take place at a time overlapping with drilling operations running simultaneously on clamped workpieces. In order to facilitate pre-centering with sufficient positional accuracy as well as simple loading and unloading of the workpiece pre-centering devices, each of the workpiece pre-centering devices in the embodiment of FIG. 2 has two axially spaced apart, each V-shaped receiving structures 222 -Direction given axial distance, it is ensured that a tilting of placed workpieces in the longitudinal direction is avoided or at least made more difficult. In addition, there is installation space between the receiving structures, which in the example is used, among other things, to accommodate the displacement drive 212. The upwardly opening V-shape of the receiving structures 222 each offers two inclined support surfaces 223 which are oriented at an angle to one another and which, for example, in the case of rotationally symmetrical workpieces, bring about automatic centering during insertion. Workpieces with a cylindrical outer contour are only in contact with the support surfaces along linearly narrow contact surfaces. Workpieces of different outside diameters can be accommodated with one and the same mounting structure. In order to nevertheless achieve an approximate centering of the workpieces that have been picked up with respect to the spindle axis, the height of the mounting structures with respect to the supporting structures of the cross slide 210 can be continuously adjusted. Plate-shaped elements, on which the V-shaped receiving structures are formed, are also easily exchangeable, so that the workpiece displacement unit 200 can be adapted in a simple manner to different workpiece dimensions.

A special feature of the cross slide 210 according to this embodiment is that the cross slide has two workpiece steady rests 260-1, 260-2 arranged at an axial distance from one another for each of the workpiece precentering devices. Each of the workpiece steady rest is designed as a self-centering workpiece steady rest and has two pivotable steady rest levers, each of which has a support roller at its free end. The workpiece steady rests can be switched between the open configuration shown in FIG. 2 and a closed configuration via suitable drives. In the open configuration, the clear distance between the facing sides of the support rollers is greater than the outer diameter of the workpiece to be inserted, so that a workpiece can be inserted into or removed from a workpiece precentering device without colliding with the workpiece steady rest. In the closed configuration, the workpiece steady rest offers exact positioning of the workpiece in relation to the assigned spindle axis as well as a support of the workpiece at the location of the workpiece steady rest, so that, particularly with very long and / or thin workpieces, the workpiece is deflected by the support provided by the workpiece steady rest can be avoided. The workpiece steady rests are each installed on the outside of the associated frame elements 232-1, 232-2 between these and the external V-shaped receiving structures of the workpiece pre-centering devices. Suitable workpiece steady rests are available as purchased parts and are therefore not described in more detail here. A workpiece displacement unit, which in addition to the workpiece pre-centering devices also has workpiece steady rests, offers several functions that are important for deep drilling, namely on the one hand the functions in connection with the workpiece change and on the other hand the functions in connection with the workpiece support during drilling operation.

All drives of the deep drilling machine 100 are controlled by a computer-numerical control unit (not shown) of the deep drilling machine, so that coordinated work movements are possible.

In connection with FIGS. 3A to 3H, a possible use of a workpiece displacement unit 200 in a two-spindle horizontal deep drilling machine will now be explained in more detail. The workpiece displacement unit 200 can be constructed identically or similarly to the workpiece displacement unit according to FIG. In each of the sub-figures, a vertical section through the cross slide 210 and the workpieces W handled with it is shown perpendicular to the spindle axes 115-1, 115-2. A workpiece with a hatched cutting plane represents a workpiece in a first position or during processing. The first position is also referred to here as the clamping position. The respective spindle axis already runs through the workpiece. A workpiece cut without hatching represents a workpiece in a second position, which in the example is a loading position. Loading and unloading is possible in this position. The workpiece is then arranged at a distance next to a spindle axis. The cross slide moves in its movement phases (horizontal arrow) parallel to the horizontal displacement direction 215 by a cross stroke 217 that is less than the spindle distance 117.The processes in the area of the first tool spindle 115-1, which are closer to the in Fig. 1 is the front visible operating side. Analog processes take place in the area of the second spindle axis.

The cycle shown begins with step S1 shown in FIG. 3A, in which the cross slide 210 is at its first end stop on the operating side. The second workpiece pre-centering device 220-2 is located in the area of the first spindle axis 115-1 in a first position P1, which would enable clamping with an inserted workpiece and is therefore also referred to as the clamping position. In the situation shown, the second workpiece pre-centering device is still empty. The first closest to the operator side Workpiece pre-centering device 220-1 is located in a first loading position P2-1, in which loading and unloading (vertical double arrow) is possible. In the example, the first workpiece pre-centering device 220-1 is loaded with a workpiece that has not yet been machined.

The cross slide then moves in the direction of displacement away from the operating side to its rear end stop, so that the situation in FIG. 3B with step S2 results. In step S2, the first workpiece pre-centering device 220-1 with the previously placed workpiece is now in the clamping position P1, in which the workpiece is pre-centered with respect to the first spindle axis 115-1. Through this transverse stroke, the second workpiece pre-centering device 220-2 is moved from the clamping position into a loading position second P2-2, which is located in the intermediate area between the two spindle axes 115-1 and 115-2. The visible workpiece steady rest 260-2 is still open. The workpiece can now be received at both ends in the assigned workpiece holders and thus centered.

In a subsequent step S3 (Fig. 3C) the workpiece steady rests on the workpiece pre-centering devices loaded with workpieces are then closed so that the workpiece is not only centered with respect to the spindle axis, but is also supported in two positions between the clamped ends, but can turn.

In step S4 shown in FIG. 3D, the workpiece clamped and centered on the first spindle axis 115-1 is machined and rotated about its axis either in the same direction as the deep drilling tool and in the opposite direction by driving the workpiece spindle on the counter-holding device. This rotary movement can be omitted with other methods. Simultaneously with this deep drilling, the second workpiece pre-centering device 220-2, which is located between the spindle axes, can now be loaded with a workpiece that has not yet been processed. If the second workpiece pre-centering device has already carried a finished workpiece, then this can be unloaded in step S4 and replaced by an unmachined part.

After completion of the drilling operation on the first spindle axis 115-1, the workpiece rotation can be ended and the associated workpiece steady rests for releasing the workpiece can be opened. This step S5 is shown in Fig. 3E.

The cross slide is then moved by means of the shift drive by the cross stroke 217 into its front end stop on the operating side (step S6 is in FIG. 3F), so that again the second workpiece pre-centering device 220-2 lies in the area of the first spindle axis 115-1. The previously processed workpiece is then in the first loading position P2-1 on the operator's side.

In the subsequent step S7 (FIG. 3G), the workpiece steady rests belonging to the second workpiece precentering device 220-2 are then closed in order to achieve workpiece support between the clamped ends.

In step S8 (FIG. 3H), the workpiece clamped on the first spindle axis 115-1 is then machined and at the same time rotated about its workpiece axis. At the same time or at a time overlapping with the machining, the already machined workpiece, which is now at the front loading position P2-1 on the operator's side, can be unloaded and replaced by a new, not yet machined blank.

In the process variant just described, the loading and unloading of the workpiece pre-centering devices in the loading position takes place in an automated manner with the aid of a robot unit (not shown). This enables the cross slide 210 to be loaded or unloaded at the same time as drilling at other positions without endangering the operator. An exemplary sequence can be described in such a way that at a certain point in time the deep drilling machine machines two workpieces synchronously. At the same time, two prefabricated parts provided with holes can be removed and then two raw parts can be fitted into the workpiece pre-centering devices that have then become free. When the main machining is finished, the drilled workpieces are relaxed and moved transversely to the main spindle direction, i.e. transversely to the longitudinal direction, using the cross slide. Then the deep hole drilling machine starts machining the previously tipped workpieces. At the same time, two finished parts can be removed and two raw parts that have not yet been drilled can be fitted. This cycle can be repeated as often as required. As a result, deep drilling can be achieved with high productivity with very little non-productive times required for loading and unloading.

The concept with the cross slide can also be used with manual loading in order to increase productivity. It should be noted that, for safety reasons, manual loading and unloading should only take place when the deep drilling machine is not in operation. Loading and unloading should therefore not take place at the same time as drilling. In the case of manual assembly, the process can be as follows. First, four raw parts are loaded into the machine in an empty workpiece displacement unit with four workpiece pre-centering devices. It can be the case that workpiece Pre-centering devices are already in a first position, that is, in a position that allows clamping. In this constellation, the first position is also a loading position.

If there are still no raw parts in a first position, then two of the raw parts are moved into their first position (clamping position), clamped and the deep drilling machine then processes two workpieces at the same time. When the main machining is finished, the workpieces are relaxed and the cross slide is moved transversely to the main spindle direction. This brings the two unprocessed blanks into their clamping position. These are now clamped on both sides and the deep drilling machine then processes the two other workpieces. When this main machining is also finished, the workpieces are relaxed again. The workpiece displacement unit then makes a transverse stroke in the direction of the operating side, where an operator can remove the four completely drilled workpieces from the machine.

The previously described embodiment of the workpiece displacement unit, thanks to the integrated workpiece steady rests, has a double function in the context of loading and unloading the deep drilling machine and in the context of workpiece support between the two clamped ends. If such a support is not necessary or desired, workpiece displacement units with a simpler structure can also be used. 4 shows an oblique perspective view of a second embodiment of a workpiece displacement unit 400 which does not have any integrated workpiece steady rests. Otherwise, the structure is similar to that of the first embodiment according to FIG. 2. The same or corresponding assemblies or components therefore have the same reference numerals, increased by 200. In contrast to the embodiment according to FIG. 2, all V-shaped receiving structures are here which are are located on one side of the cross slide, provided on a common plate-shaped component which is height-adjustable attached to the frame element of the cross slide. Otherwise, reference can be made to the previous description with regard to structure and function.

There are also embodiments in which only one workpiece steady rest is provided for each workpiece precentering device.

In the cases described here, a workpiece displacement unit for use in a deep hole drilling machine essentially consists of a base slide with a guide carriage or base slide that can be moved in the longitudinal direction of the machine bed and the cross slide carried by it, which is moved in a transverse stroke by means of a displacement drive, e.g. a hydraulic cylinder be moved back and forth between two end positions can. Workpiece steadies can optionally be provided to stabilize the rotation of long workpieces. In all embodiments, it can be provided that the cross slide including the displacement drive for the cross stroke, the adjustable pre-centering for workpiece storage (i.e. the workpiece pre-centering devices) and the workpiece steady rests, if present, are configured as a total of an exchangeable unit that can be easily removed by loosening a few screws Loosen the basic slide and can be replaced by another exchange unit of other types. The deep drilling machine with integrated workpiece displacement unit can thus be quickly converted to workpieces of other dimensions and / or other civil engineering processes.

Embodiments of the invention can be used in different drilling methods, in particular in deep drilling machines that are set up for ELB deep drilling or BTA deep drilling or ejector deep drilling. With ELB deep drilling, cooling lubricant is supplied through one or more coolant channels inside the drill. The mixture of cooling lubricant and chips is discharged through a longitudinal groove or bead on the outside of the tool shank. With BTA or STS deep drilling, the cooling lubricant is supplied from the outside via a special cooling lubricant supply device. The cooling lubricant is pumped under pressure into an annular space between the outside of the drilling tool and the inside wall of the bore. The cooling lubricant and chips are returned through a coolant channel provided inside the deep drilling tool. Ejector deep drilling is a variant of BTA deep drilling.

Claims

1. Deep drilling machine (100) comprising:

a machine bed (102) carrying a linear guide system (104);

a tool spindle unit (110) which can be moved linearly on the linear guide system (104) and has at least one tool spindle (112) which can be rotated about a spindle axis (115) by means of a spindle drive (113) and a tool holder (116) for holding a drilling tool having;

a counter-holding unit (120) which, on a side facing the tool spindle unit (110), has a workpiece holder (126) for receiving a first end section of a workpiece (W);

a workpiece receiving unit (130) arranged between the tool spindle unit (110) and the counter-holding unit (120), the workpiece receiving unit (136) on the side facing the counter-holding unit (120) for receiving the second end section of the workpiece (W) opposite the first end section and a Has through opening for passing through the drilling tool;

marked by

a workpiece displacement unit (200), which is arranged between the counter-holding unit (120) and the workpiece receiving unit (130) and has a cross slide (210) which, by means of a displacement drive (212), moves in a direction of displacement perpendicular to the spindle axis (115) ( 215) can be moved back and forth,

wherein the cross slide (210) has a first workpiece pre-centering device (220-1) and a second workpiece pre-centering device (220-2) parallel thereto, which by moving the cross slide (210) parallel to the direction of displacement (215) between a first position (P1) and at least one second position (P2) can be moved back and forth,

wherein the workpiece pre-centering devices (220-1, 220-2) are designed such that a workpiece (W) carried by a workpiece pre-centering device is aligned essentially ready for drilling to the spindle axis (115) when the workpiece pre-centering device is in the first position (P1) and accessible for a loading operation next to the spindle axis (115) when the workpiece pre-centering device is in the second (P2).

2. Deep drilling machine according to claim 1, characterized in that

a cross stroke (217) of the cross slide (210) is designed so that in addition to the spindle axis (115-1, 115-2) on two opposite sides of the spindle axis (215) in each case a second position (P2-1, P2-2 ) exists.

3. Deep drilling machine according to claim 1 or 2, characterized in that

the tool spindle unit has at least two tool spindles which are rotatable about mutually parallel spindle axes (115-1, 115-2) which are at a spindle distance (117) from one another in a preferably horizontal spindle plane (118);

the counter-holding unit (120) has a workpiece holder (126-1, 126-2) for each tool spindle,

the workpiece holder unit (130) for each tool spindle a workpiece holder (116-1, 116-2) and a feed-through opening for

Having passing a drilling tool; and

the cross slide (210) can be moved back and forth parallel to the spindle plane (118) by means of the displacement drive (212) and for each of the tool spindles a first workpiece pre-centering device (220-1) and a second workpiece pre-centering device (220- parallel thereto) 2), each of which can be moved back and forth between a first position and at least one second position by moving the cross slide in the direction of displacement (215).

4. Deep drilling machine according to claim 3, characterized in that

a cross stroke (217) of the cross slide (210) is smaller than the spindle distance (117), so that at least one second position (P2-2) lies in an intermediate area between the spindle axes (115-1, 115-2).

5. Deep drilling machine according to one of the preceding claims, characterized in that

the counter-holding unit (120) for each tool spindle has a workpiece spindle (122-1, 122-2) which can be rotated axially parallel to it and to which the workpiece holder (126-1, 126-2) is attached, with an axis of rotation of the workpiece spindle being coaxial with the spindle axis or is arranged offset parallel to this.

6. Deep drilling machine according to claim 5, characterized in that

each workpiece spindle (122-1, 122-2) is assigned its own spindle drive (123-1, 123-2) for active rotation of the workpiece spindle.

7. Deep drilling machine according to one of the preceding claims, characterized in that

the workpiece pre-centering devices (220-1, 220-2) can be adjusted with respect to their position on the cross slide (210).

8. Deep drilling machine according to one of the preceding claims, characterized in that

a workpiece pre-centering device (220-1, 220-2) has two receiving structures (222) which are arranged axially offset from one another and each has two bearing surfaces aligned at an angle to one another such that the receiving structures widen upwards.

9. Deep drilling machine according to one of the preceding claims, characterized in that

the workpiece displacement unit (200) has a base slide (202) which can be moved linearly on the linear guide system (104), the base slide carrying the cross slide (210).

10. Deep drilling machine according to claim 9, characterized in that

the cross slide (210) and the workpiece pre-centering devices (220-1, 220-2) form components of an interchangeable unit which is attached as an interchangeable assembly to the base slide (202).

11. Deep drilling machine according to one of the preceding claims, characterized in that

the cross slide (210) for each of the workpiece precentering devices (220-1, 220-2) has at least one workpiece steady rest (260-1, 260-2), with each of the workpiece precentering devices preferably having two axially offset workpiece steadies (260-1 , 260-2) are assigned.

12. Deep drilling machine according to claim 11, characterized in that the workpiece steady rests (260-1, 260-2) are designed as self-centering workpiece steady rests, in particular with support rollers, so that the workpiece can rotate in the workpiece steady rest during drilling.

13. Deep drilling machine according to claim 11 or 12, characterized in that the workpiece steady rests (260-1, 260-2) can be automatically switched between an open configuration and a closed configuration, wherein in the open configuration a workpiece is inserted into the workpiece pre-centering device or a removal from it is possible and at the transition from the open configuration to the closed configuration the workpiece steady rest takes over the workpiece and supports it in a position centered on the spindle axis.

14. Deep drilling machine according to one of the preceding claims, characterized by an automatic loading device assigned to the deep drilling machine for the automated loading and unloading of workpiece pre-centering devices located in a second position, the loading device preferably comprising a robot unit.