Honing machine

Abstract

Honing machine (100) for honing a bore in a workpiece, comprising: a machine-resistant support structure (120); at least one honing unit (130) mounted on the support structure (120), which has a spindle unit (150) in which a spindle shaft (152) is rotatably mounted, wherein the spindle shaft (152) is rotatable about a spindle axis (155) by means of a rotary drive (450) and has a device for attaching an expandable honing tool at a tool-side end (153), a lifting drive to generate a lifting movement of the spindle unit (150); a widening drive (550) for widening the honing tool, wherein the widening drive (550) is coupled to an adjustment rod (460) running inside the spindle shaft (152); wherein the spindle unit (150) has a spindle unit housing (310) which has a first housing section (310-1) for receiving the rotary drive (450) and a second housing section (310-2) for receiving the expansion drive (550), characterized by the fact that the rotary drive (450) is contained in an interchangeable first cartridge (400) and the expansion drive (550) is contained in a second cartridge (500) that can be interchanged independently of the first cartridge (400), wherein the first cartridge (400) can be inserted into the first housing section (310-1) and the second cartridge (500) can be inserted into the second housing section (310-2).

Description

SCOPE OF APPLICATION AND STATE OF THE ART

[0001] The invention relates to a honing machine according to the preamble of claim 1 for honing a bore in a workpiece.

[0002] Honing is a machining process with geometrically undefined cutting edges, in which a honing tool performs a two-component cutting motion and maintains constant surface contact between one or more cutting material elements, such as honing stones, of the honing tool and the bore's inner surface being machined. The kinematics of a honing tool are characterized by a superposition of a rotary motion and a stroke motion in the axial direction of the bore. An optional expansion motion is usually also included, which results in a change in the effective diameter of the honing tool.

[0003] A single stroke of the honing tool within the bore, consisting of an insertion and subsequent withdrawal, is called "mandreling." A repeated stroke within the bore, i.e., insertion, followed by a cyclical back-and-forth movement within the bore, and finally withdrawal, is called "oscillation." Oscillating honing processes typically require a reaming motion, as the effective diameter of the honing tool is actively changed during oscillation. Additionally, the reaming motion usually compensates for wear on the cutting tool body.

[0004] On the inner surface of the bore, the kinematics of the honing tool create a surface structure with intersecting machining marks. Surfaces finished by honing can meet extremely high requirements regarding dimensional and form tolerances, and in some cases exhibit a special surface roughness and structure, such as a plateau surface, which combines low wear due to a high material bearing area with the ability to maintain an oil film for lubrication. Therefore, many highly stressed sliding surfaces in engines or engine components, e.g., cylinder bores in engine blocks or inner bore surfaces in injection pump housings, are finished by honing.

[0005] A honing machine is a machine tool suitable for honing bores in workpieces. It has at least one honing unit mounted on a machine-fixed support structure, such as a stand, column, or frame. A honing unit comprises a spindle unit in which a spindle shaft is rotatably mounted. The spindle shaft is rotatable about its axis by means of a rotary drive and has a device for attaching a honing tool at one end, on the tool side. A stroke drive is provided to generate the stroke movement of the spindle unit parallel to the spindle axis. In honing machines of this type, a reaming drive is also provided for expanding the honing tool. The reaming drive is coupled to an infeed rod running inside the spindle shaft.

[0006] To optimize the efficiency and quality of honing processes, highly dynamic direct drives for stroke and rotation are increasingly being used, enabling honing operations with high stroke speeds (currently, for example, up to approx. 100 m / min) and rotational speeds (currently, for example, up to approx. 5000 rpm).

[0007] Direct drives are known for the highly dynamic movement of machine parts. Direct drives are characterized by their potential to enable high speeds and accelerations of the driven machine axis while simultaneously generating virtually frictionless motion. DE 10 2016 200 295 A1 describes a honing machine whose linear drive is an electric linear motor. The expansion drive is also an electric direct drive. The spindle unit has a housing comprising a first housing section for accommodating the rotary drive and a second housing section, integrally formed with the first housing section, for accommodating the expansion drive.

[0008] The expansion drive and the rotary drive are subject to wear, particularly in the area of ​​the ball bearings. Therefore, after several years of operation of the honing unit, the rotary drive, the expansion drive, or both assemblies may need to be overhauled. To reduce downtime of the honing machine, a second rotary drive or a second expansion drive is often procured as a spare part and installed in place of the worn drive.

[0009] It may be necessary to realign the machine geometry when replacing the rotary drive. This is time-consuming and requires a well-trained operator. While the expansion drive and other components of the expansion system can be replaced independently, the expansion mechanism is attached to the spindle motor. Replacing the spindle motor necessitates either first removing the expansion and then reinstalling it, or removing the entire assembly of spindle motor and attached expansion together, which is inconvenient due to its weight. In both cases, all connections of the expansion drive to the machine (electrical lines, coolant, sensors) must be disconnected, even if the expansion drive itself is not being replaced.

[0010] German patent application DE 20 2011 003 069 U1 discloses a device for the mechanical surface treatment of workpieces, in particular for honing, comprising a machine base with a top surface, a machine upper section with a bottom surface, wherein the machine upper section has a vertical column which, in an upper column region, has on its outer surface facilities for receiving at least one machining unit equipped with a tool spindle for mechanical surface treatment, and a ring table with a bottom surface, wherein the ring table is arranged around the column in a lower column region and has a fixture carrier rotatable about a vertical axis of rotation for receiving at least one workpiece holding device. The ring table and the machine upper section are each arranged with their undersides on the top surface of the machine base and are fixedly mounted on the machine base. TASK AND SOLUTION

[0011] The invention is based on the objective of providing a honing machine that is particularly easy to assemble for initial assembly and particularly easy to repair and maintain for any necessary maintenance and repair work.

[0012] To solve this problem, the invention provides a honing machine with the features of claim 1. Advantageous embodiments are specified in the dependent claims. The wording of all claims is incorporated herein by reference into the description.

[0013] According to one formulation of the invention, a honing machine of the generic type is characterized in that the rotary drive is housed in an interchangeable first cartridge and the expansion drive is housed in a second cartridge that can be interchanged independently of the first cartridge, wherein the first cartridge can be inserted into the first housing section and the second cartridge into the second housing section.

[0014] The term "cartridge" here refers to an interchangeable assembly that combines all components to be replaced during the replacement process into a single unit and has its own housing (cartridge housing). Accordingly, the first cartridge has a first cartridge housing, which contains, among other things, the rotary drive, and the second cartridge has a second cartridge housing, which contains, among other things, the expansion drive. This results in a modular design of the spindle unit, in which the mutual alignment of the first and second cartridges, and thus of the rotary drive and the expansion drive, is ensured by their installation in the shared spindle unit housing. This housing serves as a common geometric reference for the installed components.Additionally, the spindle unit housing allows for a connection to the components of the linear guide of the lifting drive, thus simplifying or eliminating certain alignment work.

[0015] Housing the rotary drive and the expansion drive in independently replaceable cartridges offers several advantages, including the ease of maintaining tight manufacturing tolerances. These tight tolerances typically eliminate the need to readjust the machine geometry after a replacement. This significantly simplifies and accelerates repair and / or maintenance work, which can then be performed by well-trained personnel who do not need to be specialists in component alignment. The arrangement of the first and second cartridges within the shared spindle unit housing allows for independent replacement of the rotary drive (spindle motor) and the expansion drive.

[0016] The first cartridge and / or the second cartridge preferably have a substantially rotationally symmetrical outer contour. Mechanical orientation structures may be provided to ensure that the cartridges can only be mounted in the spindle unit housing in a specific rotational position.

[0017] In preferred embodiments, the spindle unit housing is designed as a monocoque housing, in which the first and second housing sections are formed integrally. This eliminates potentially critical alignment interfaces between the housing sections. A one-piece spindle unit housing can provide the spindle unit with additional stability and ensures a consistent geometric relationship between the housing sections and, if applicable, the cartridges housed therein. The spindle unit housing can optionally also be composed of several housing parts.

[0018] It is possible in principle to design the assembly so that the first and second cartridges can be installed into the spindle unit housing from the same side. However, in preferred embodiments, the first and second cartridges can be inserted into the spindle unit housing from opposite sides. This facilitates independent disassembly and assembly. With a vertically oriented spindle unit, the first cartridge, which contains the spindle motor, can be mounted from below, while the second cartridge, which contains the expansion drive, is inserted into the spindle unit housing from above.

[0019] In some embodiments, at least one first mating surface is formed on an inner side of the first housing section. This mating surface, in contact with at least one corresponding mating surface on the first cartridge, positions and aligns the first cartridge within the first housing section. Alternatively or additionally, at least one second mating surface is formed on an inner side of the second housing section. This mating surface, in contact with at least one corresponding mating surface on the second cartridge, positions and aligns the second cartridge within the second housing section. The position and alignment can be determined by mating diameters located on the outer diameter of the cartridges.In some embodiments, it is considered particularly advantageous that an internal fit is designed with a smaller diameter than an external fit located on a flange, so that during assembly and disassembly the respective mating surfaces only come into contact with each other when the respective cartridge is almost completely inserted into the spindle unit housing, and not already at the beginning of the insertion into the spindle unit housing.

[0020] Furthermore, axial stop surfaces can be formed on the spindle unit housing to define the axial position of the first cartridge in the first housing section and the second cartridge in the second housing section. In some embodiments, outwardly projecting flange sections are provided on the cartridges, which abut corresponding end faces of the spindle unit housing when the respective cartridge is inserted and the desired axial installation position is reached. The respective axial fastening, i.e., the determination of the axial position of each cartridge relative to the spindle unit housing, can thus be achieved via a flange with axial screws.

[0021] In many designs, it is relatively easy to directly contact the expansion drive or the second cartridge from the outside, thereby supplying and discharging the resources required for operation (electrical power, if necessary, exchange of electrical signals for control and transmission of encoder signals, fluidic media). However, since contacting the first cartridge from the side of the honing tool connection is not possible or only possible under unfavorable conditions, the first cartridge should ideally also be contacted through the spindle unit housing.In some embodiments, connections for any rotary encoders that may be present, the electrical connections for supplying electrical power to the motor winding and / or connections for fluids (coolant for dissipating motor heat, coolant supply line and coolant return line to the machining point, if necessary sealing air) should preferably be arranged on the side of the first cartridge facing the second cartridge.

[0022] In some embodiments, connection problems are solved particularly conveniently by arranging corresponding connecting elements of at least one plug connection for transmitting liquid or gaseous fluid, electrical power, and / or electrical signals on one side of the first cartridge facing the second cartridge, as well as on one side of a housing section of the spindle unit housing facing the first cartridge. Because of the plug connection design, the required connection is made automatically during assembly of the components, so that no separate assembly steps for establishing electrical and / or fluidic connections are necessary. The plug connection design also makes replacing the first cartridge significantly faster and easier than if several lines had to be individually disconnected and reconnected.

[0023] The cartridge concept can be implemented with different drive types, including rotary and / or expansion drives. According to a further development, a torque motor is used as the expansion drive, which is integrated directly into the second cartridge housing. This allows the expansion drive to be as short and therefore as lightweight as possible. The torque motor can be coupled to a rotary encoder, preferably a high-resolution, multi-turn absolute encoder. The rotating part of the torque motor can drive a lead screw to convert the rotary motion into a linear motion, which then acts on the feed rod running inside the lead screw shaft.

[0024] The torque motor is an example of an electric direct drive. Alternatively, the drive can also be another electric direct drive, such as a voice coil motor, which does not require a lead screw or similar component to convert the direction of movement. It is also possible to use a servo motor as a rotary drive.

[0025] To further facilitate assembly, maintenance, and repair work, some embodiments feature fluid channels in the cartridge housing of the first cartridge for the passage of fluid, particularly cooling fluid for the rotary drive. This allows the cartridge housing of the first cartridge to be cooled directly, and the heat to be dissipated from the rotary drive area via the cartridge housing. This may eliminate the need for a cooling device on the rotary drive itself. As a result, the rotary drive can be built compactly and then removed together with the first cartridge without requiring a service technician to disconnect any hose connections.

[0026] Alternatively or additionally, fluid channels for conveying fluid can be provided in the spindle unit housing. For example, fluid channels can be provided for conveying cooling fluid to the rotary drive. This allows the spindle unit housing to be cooled directly, and the heat can be dissipated via the spindle unit housing, for example, from the rotary drive area. This may eliminate the need for a cooling system and / or coolant channels on the first cartridge and / or on the rotary drive itself. Alternatively or additionally, fluid channels can be provided for conveying fluid to and from the honing tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Further advantages and aspects of the invention will become apparent from the claims and from the following description of preferred embodiments of the invention, which are explained below with reference to the figures. Fig. Figure 1 shows an oblique perspective view of a honing machine according to an exemplary embodiment; Fig. Figure 2 shows a vertical section through a honing unit arranged on the support structure of the honing machine and components of a rotary table transport system; Fig. Figure 3 shows a section along the yz-plane through an adjustment unit of an alignment system according to an exemplary embodiment: Fig. Figure 4 shows a section parallel to the xy-plane through the adjustment unit. Fig. 3 Fig. Figure 5 shows an exploded view of the setting unit of the Fig. 3 and Fig. 4; Fig. Figure 6 shows the replacement of components of an expansion system in which the expansion drive is arranged in a replaceable cartridge; Fig. Figure 7 shows the replacement of the spindle shaft and other components of the spindle unit, with the rotary drive being arranged in a replaceable cartridge; Fig. Figure 8 shows an oblique perspective view of the cartridge containing the rotary drive, which has plug connectors on its upper side for the electrical and fluidic connection of components of the cartridge; and Fig. Figures 9A to 9D show special features of the available stroke length and stroke positions of the embodiment. DETAILED DESCRIPTION OF THE EXECUTION EXAMPLES

[0028] The Fig. Figure 1 shows an oblique perspective view of a honing machine 100 according to an exemplary embodiment. Fig. Figure 2 shows a vertical section through a honing unit mounted on the support structure of the honing machine and components of a rotary table transport system. In the configuration shown, the honing machine has only a single honing unit. A second support structure with a second honing unit for machining the same workpieces can be provided.

[0029] The honing machine 100 has an essentially rectangular machine base 110 with a frame and a base plate, which is, or should be, horizontally aligned when the honing machine is fully set up. The rectangular base plate is slightly longer in the first direction (longitudinal direction), which runs parallel to the y-axis of the machine coordinate system (MCS), than in the second direction (transverse direction), which runs perpendicular to it and parallel to the x-axis of the machine coordinate system (transverse direction). Near the rear 114 of the machine base, close to one of the longitudinal edges, a vertical stand 120 is arranged, which is firmly bolted to the machine base. The vertical stand serves as a support structure 120 for a honing unit 130, which is mounted on the front of the support structure.

[0030] A key component of the honing unit is a spindle unit 150, in which a spindle shaft 152 is rotatably mounted. A rotary drive or spindle motor is integrated into the spindle unit to drive the spindle shaft, which can drive the spindle shaft around the spindle axis 155, i.e., around the axis of rotation of the spindle shaft 152, with a predefined speed profile. The spindle shaft 152 has a device (tool holder) at a tool-side end 153, also referred to as the spindle nose, for attaching a honing tool 190.

[0031] The spindle unit 150 is mounted on the top or front surface of a slide plate 165. The slide plate is supported by a slide housing 160, which serves as the base support for the honing unit. A linear guide system (not visible in the illustrations) is provided between the base support 160 formed by the slide housing and the slide plate 165, or rather the spindle unit supported by it, to guide a linear stroke movement of the spindle unit 150 relative to the base support 160. In this example, the stroke drive comprises an electric linear motor with a primary and a secondary part, which are movable relative to each other parallel to the longitudinal direction of the linear guide system (ideally also parallel to the spindle axis 155).

[0032] In this example, the electrically powered primary part is mounted on the side of the slide plate or the also electrically powered spindle unit 150, while a series of permanent magnets is arranged inside the base carrier 160. A reverse arrangement is also possible.

[0033] The linear guide system has guide rails attached to the base support 160. The corresponding guide shoes are arranged on the underside of the carriage plate 165. There are also embodiments in which the guide shoes, which slide on the guide rails, are attached to individual mounting surfaces of the spindle unit without the interposition of a carriage plate common to the guide shoes.

[0034] The honing machine 100 is equipped with a workpiece transport system 180, which includes a rotary table or rotary indexing table. The illustrated rotary table transport system features a horizontally oriented table top 184, which can be rotated by predefined angular increments around a nominally vertical (parallel to the z-direction of the machine coordinate system) rotation axis 185 by means of a rotary drive located below the table top. Several (in this example, six) workpiece holders 182 are provided on a pitch circle around the rotation axis 185, each designed to hold a workpiece W. During transport, the table top rotates by a specific angle (here 60°) around the stationary rotation axis 185 to successively position each workpiece W in a machining position under the honing unit 130 such that the spindle axis 155 aligns as closely as possible with the bore axis in the workpiece W.Ideally, all workpiece fixtures are mounted at approximately the same distance from the axis of rotation 185 and at approximately the same circumferential distance to each other. If several honing units or honing stations are operated using the rotary table transport system 180, all honing units must be aligned so that, in every transport position, the distance between the actual axis of rotation of the spindle motor and the bore axis in the workpiece is as small as possible. This means that all honing units in the honing machine must be aligned accordingly.

[0035] The honing unit 130 is attached to the front of the stand or support structure 120 by means of two fastening units 210-1, 210-2. The fastening units provide a mechanical connection between the machine-mounted stand 120 (support structure 120) and the base support 160 of the honing unit 130. The vertical distance 212, measured in the z-direction, between the effective centers of the fastening units 210-1, 210-2 is, in this example, more than 30%, in particular more than 40% and / or less than 90% or less than 80% of the vertically measured length of the base support 160. The fastening units are not located at the outer ends of the base support 160, but are offset inwards.A particularly advantageous arrangement is one in which the mounting units are positioned such that the guide shoes, located on the slide plate supporting the spindle unit, are as close as possible to the mounting units when the spindle unit is in a stroke position intended for machining. This allows the dynamic forces occurring during an oscillating stroke movement to be absorbed particularly well.

[0036] The mounting units 210-1 and 210-2 simultaneously function as the first adjusting unit 210-1 and second adjusting unit 210-2 of an alignment system 200, the components of which are at least partially arranged between the support structure 120 and the base support 160. Using the alignment system 200, it is possible to continuously and reversibly adjust both the position of the spindle axis 155 along two mutually perpendicular translational axes and the orientation (angular position) of the spindle axes with respect to two mutually perpendicular rotational axes. This makes it possible to align the entire spindle unit so that its axis (spindle axis 155) is aligned as closely as possible with the axis of the bore to be machined.

[0037] Each of the adjustment units 210-1, 210-2 offers exactly two translational adjustment degrees of freedom. According to the first adjustment degree of freedom, the height of the adjustment unit, measured parallel to the first direction (y-direction), can be continuously and reversibly changed within certain limits, so that the distance 214, measured parallel to the first direction, between the support structure 120 and the base support 160 of the honing unit at the location of the mounting unit can be changed. First adjustment elements are provided for this purpose. According to the second adjustment degree of freedom, it is possible to continuously and reversibly displace the components of the adjustment unit that are fixedly connected to the base support 160 of the honing unit 130 relative to those components that are fixedly connected to the support structure 120, parallel to the second direction (x-direction). Second adjustment elements are provided for this purpose.There are components that belong to both the first and second adjustment elements and therefore have a dual function (e.g., a wedge element that will be explained later).

[0038] These two translational adjustment degrees of freedom, combined with the fact that the two adjustment units 210-1, 210-2 are arranged at a vertical distance 212 (measured along the z-direction and the third direction, respectively), make it possible to adjust the position of the spindle axis 155 along two mutually perpendicular translational axes (parallel to the first direction and parallel to the second direction) and, independently of this, to continuously and reversibly adjust the orientation of the spindle axis 155 with respect to two mutually perpendicular rotational axes (each parallel to the first direction and to the second direction).

[0039] If, for example, both adjustment units 210-1 and 210-2 are adjusted in their effective height such that the distance 214, measured parallel to the first direction, between the support structure 120 and the base support 160 is changed by the same amount, the position of the spindle axis 155 changes due to parallel displacement in a yz-plane, or a translation of the spindle axis 155 in the first direction. This corresponds to a pure change in position without a change in orientation.

[0040] If no distance change or a different distance change is set on the first setting unit 210-1 than on the second setting unit 210-2, this results in a change in the inclination of the spindle axis 155 within the yz-plane, which leads to a rotation of the spindle axis about a virtual axis of rotation that runs parallel to the second direction perpendicular to the yz-plane (x-direction). This results in a change of orientation.

[0041] If a displacement parallel to the second direction (x-direction) is set on both the first adjusting unit 210-1 and the second adjusting unit 210-2 by the same displacement path, this results in a parallel displacement of the spindle axis in an xz-plane or a translation of the spindle axis 155 in the second direction. This corresponds to a pure change in position without a change in orientation.

[0042] If unequal displacement paths are set on the first setting unit 210-1 and on the second setting unit 210-2, this results in a tilting adjustment of the spindle axis in an xz-plane, which corresponds to a rotation about a virtual axis of rotation that runs parallel to the first direction.

[0043] The spatial position of any resulting virtual rotation axes is not fixed, but varies depending on the ratios of the changes made to the two adjustment units.

[0044] The following will now be discussed with additional reference to the Fig. Sections 3 to 5 explain in more detail the construction of the first adjustment unit 210-1 or the first fastening unit 210-1 of the alignment system 200. This section shows Fig. 3. Make a section along the yz-plane through the adjustment unit, Fig. Figure 4 shows a section parallel to the xy-plane and Fig. Figure 5 shows an exploded view of the first setting unit 210-1. The second setting unit 210-2 can be constructed identically or almost identically.

[0045] The adjusting unit 210-1 comprises a multi-component base element 220, designed for fixed mounting on the support structure 120 of the honing machine or on an adapter unit fixedly connected to the support structure. Furthermore, a wedge element 230 is provided, which has a flat first wedge surface 231 facing the base element 220 and a flat second wedge surface 232, which, in the assembled state, faces the base support 160. The wedge surfaces 231, 232 of the relatively flat wedge enclose a wedge angle 233 of approximately 5° to 6°. In the assembled state, the flat first wedge surface 231 rests flat against a flat sliding surface 221 of the base element 220 facing it.A relative displacement of the wedge element 230 relative to this sliding surface 221 of the base element along a displacement direction 238 parallel to the x-direction (second direction) is provided by design; relative movements in other directions are prevented by design. The actuating devices provided for this relative displacement, for displacing the wedge element 230 in the displacement direction and for positioning the wedge element in a target position, will be explained later.

[0046] The base element 220 includes a ball socket 222, which serves as the base of the mounting unit and is designed to be securely screwed to the support structure of the honing machine at the designated mounting position. In some embodiments, an adapter unit with suitable mounting interfaces is interposed between the ball socket and the support structure. A cylindrical pin can be used to orient the ball socket 222 on the support structure 120 or on an adapter provided for connection to the support structure. This cylindrical pin can define the rotational position of the ball socket in a locating bore of the support structure or adapter.

[0047] A spherically curved sliding surface 223 is formed on the side facing the wedge element. In the assembled state, a spherical disk 224 rests in the ball socket 222. This disk has a convex spherical sliding surface 225 corresponding to the sliding surface 223 on the side facing the ball socket and a flat sliding surface 221 on the side facing the wedge element. Free rotation of the spherical disk 224 in the ball socket 222 is prevented by the fact that the ball socket has two cylindrical pins 228 which run in a groove in the spherical disk 224. Thus, only limited rotation about an axis of rotation parallel to the second direction is possible.

[0048] During assembly, the wedge element 230 is placed on the spherical disc 224. This wedge element can be moved laterally in the displacement direction (parallel to the x-direction) to allow stepless and reversible adjustment of the height of the adjusting element, measured parallel to the y-direction. On the one hand, the angle of the wedge element 230 should be shallow enough to allow it to move within the self-locking range. This means that a change in load on the wedge element should not cause it to move laterally. On the other hand, the angle of the wedge element should also be steep enough to provide a sufficient adjustment range in height for the available lateral displacement of the wedge element 230.In the exemplary embodiment, the wedge angle 223 is dimensioned such that an integer ratio exists between a lateral displacement of the wedge element and the resulting change in height of the fastening unit or the adjustment unit. A wedge with a corresponding ratio of 1:10 has proven to be well suited, so that a displacement of 1 mm causes a change in height of 0.1 mm.

[0049] To facilitate handling of the components during assembly, two tie rods 229 are provided. These each exert a slight pressure on the wedge element 230 via a coil spring, so that it rests on the ball disc 224 and thus prevents the wedge element from lifting off the ball disc during assembly.

[0050] A substantially cuboid-shaped retaining block 226 is fixedly mounted in the ball socket 222. A support bolt 227 is seated in the retaining block. When the honing unit 130 is attached to the mounting unit 210-1, the base support 160 rests on this support bolt to counteract the mass of the honing unit against gravity during assembly. The support bolt 227 has a rounded outer contour on its side facing the honing unit. The base support 160 has a rectangular pocket or recess 162 on its side facing the mounting unit to receive the support bolt. Ideally, when received, the support bolt forms line contact (or point contact in the case of larger inclinations) with the rectangular pocket, so that no stress is exerted even when the honing unit is tilted.

[0051] On the upper mounting unit 210-1, the support bolt 227 is fitted relatively tightly into this pocket on the base support 160 in order to determine the position of the honing unit in the honing machine relatively precisely during assembly. On the lower mounting unit 210-2, the pocket on the base support 160 of the honing unit is somewhat larger, so that no constraint is exerted on the honing unit here either.

[0052] The wedge element 230 has threaded bores on opposite sides of the rectangular recess intended for the passage of the retaining block 226. These bores are oriented essentially parallel to the second direction. Adjusting screws 240-1 and 240-2 are screwed into these threaded bores. These screws serve as actuating elements for an actuating device that moves the wedge element 230 within the displacement device 238. Using these adjusting screws, the wedge element can be moved relative to the (machine-fixed) retaining block 226 in the displacement direction 238. Moving the wedge element causes the height of the fastening element to be adjusted, and thus the distance (in the y-direction) between the support structure and the base of the honing unit to be adjusted at the location of the adjustment unit. Once the desired target position is reached, the wedge element automatically holds this position due to self-locking.However, the wedge element can be further fixed in this position by tightening the opposing adjusting screws.

[0053] On the base body 160, a flat inclined surface 164 is formed at the location intended for attaching the mounting unit or adjustment unit 210-1. In the assembled state, this inclined surface acts as a sliding surface in conjunction with the second wedge surface 232. Threaded bores extending parallel to the x-direction are also provided in the base support 160 of the honing unit. Adjusting screws 250-1 and 250-2 are seated in these bores. These screws are also supported by the (machine-fixed) retaining block 226. By actuating the adjusting screws 250-1 and 250-2, the base support 160 of the honing unit can be displaced relative to the machine-fixed support structure 120 in a direction of displacement 238. During this movement, the flat second wedge surface 232 and the opposite flat inclined surface 164 slide against each other on the base support. Since this results in a minimal change in distance in the y-direction, the adjusting screws 240-1 and 240-2 should also be adjusted to the same extent for compensation.

[0054] An advantageous design is one in which a fixed amount of displacement is achieved per revolution of the adjusting screw. For example, with a thread pitch of 1 mm, a full revolution of adjusting screw 250-2 results in a displacement of 1 mm. By measuring the relative positions of the parts, the current position can be read and the remaining required adjustment range can be estimated.

[0055] The basic setting of the mounting units 210-1, 210-2 is the theoretical center position, such that, assuming all manufacturing tolerances of the honing machine are absent, the axis of the spindle motor, i.e., the spindle axis 155, would be perfectly aligned with the bore axis in the workpiece in this position. Starting from this central position, both the height of the mounting units parallel to the first direction (y-direction) and the lateral offset by relative displacement parallel to the second direction (x-direction) can be independently and reversibly adjusted using the adjusting screws 240-1, 240-2 and 250-1, 250-2, respectively. A lateral displacement parallel to the x-direction is achieved by adjusting screws 250-1, 250-2 in the base support. The height of the mounting unit in the y-direction is adjusted by adjusting screws 240-1, 240-2 in the wedge element 230.

[0056] To change the position of the honing unit relative to the bore axis in the workpiece, the upper adjusting unit 210-1 and the lower adjusting unit 210-2 are adjusted in the same direction by the same amount. To adjust the angular position of the unit, the upper and lower adjusting units are adjusted in opposite directions and / or by different amounts. When adjusting the mounting units in opposite directions and / or by different amounts, the different heights of the two adjusting units can cause an angular misalignment between the wedge surfaces of the wedge elements that rest on the ball caps. This angular misalignment can be compensated for by small adjustments of the ball discs in the ball sockets.Thus, the spherical bearings integrated into the mounting units 210-1, 210-2, which have complementary curved sliding surfaces, serve as an angular compensation device for automatically compensating for angular misalignments and any resulting stresses under unfavorable adjustment conditions of the adjustment units. In this example, the radius of curvature of the spherical sliding surfaces 223, 225 is selected such that (when the wedge element is set to its central position) the center of the sphere lies on the axis of rotation of the spindle motor, i.e., on the spindle axis 155. This ensures that any compensating movements do not affect the position and orientation of the spindle axis.

[0057] A method for adjusting the machine geometry with alignment of the spindle axis in relation to the bore axis of the bore to be honed can proceed as follows, for example.

[0058] First, the fastening units 210-1 and 210-2, which serve as adjustment units, are attached to their designated positions on the front of the support structure using screws. The wedge elements and the ball discs are each moved into a central position.

[0059] The honing unit is then attached by placing it onto the support bolts 227 at the top and bottom. The base support 160 of the honing unit 130 is then moved into a central position.

[0060] For an alignment operation, the workpiece holder should have a cylindrical geometry that is as long as possible and referenced to the workpiece holder or the transport system. For example, a master cylinder can be mounted as an alignment aid at the location of a workpiece holder on the rotary table transport system. The cylindrical bore in the master cylinder thus represents the bore axis in the workpiece and establishes the reference to the transport system. This step can be performed before or after the honing unit is attached to the support structure.

[0061] The parallelism of the spindle motor's axis of rotation, i.e., the parallelism of the spindle axis to the central longitudinal axis of the master cylinder, can then be adjusted, for example, by adjusting the adjusting units in opposite directions and / or with unequal force. Preferably, the lateral adjustment (parallel to the direction of displacement) is made first using the adjusting screws in the base, and then the frontal adjustment is made by moving the wedge elements.

[0062] Afterwards, the master cylinder can be disassembled in order to measure any possible positional offset of the spindle axis from the target position directly at those bores of the transport system in which the workpiece fixtures will later be mounted.

[0063] If these measurements reveal a still required positional offset, the position of the spindle motor's axis of rotation relative to the workpiece's bore axis is adjusted by moving the adjusting elements in the same direction by equal amounts. Here too, the lateral position (position in the x-direction) is preferably adjusted first, followed by the frontal position (position along the first direction or y-direction).

[0064] Once the desired target position and orientation have been achieved with sufficient accuracy, the adjusting screws of the setting units are tightened without further relocation of the components actuated by them, in order to fix the relative positions achieved.

[0065] As shown, the support structure can be, for example, a vertical stand that may only support a single honing unit. A honing machine can have two or more such stands. The support structure can also be a column on whose circumference several honing units are mounted offset (see DE 20 2011 003 069 U1). Instead of the direct mounting of the fastening units to the support structure shown, indirect fastening using an adapter designed for connection to the support structure is also possible.

[0066] Based on the Fig. Sections 6 to 8 now describe special features of the design of a spindle unit 300, which is provided in some embodiments. The spindle unit 150 of the embodiments described so far can be identical in design to the spindle unit 300 described below. However, it is also possible that the spindle unit 150 has a different design than the spindle unit 300 described now. Apart from the spindle unit, the components shown are given the same reference numerals as in the preceding examples.

[0067] The spindle unit 300 has a modular design. The spindle unit housing 310 is designed as a single-piece component and is also referred to here as a monocoque housing. The component, open at both ends and essentially tubular, has a first housing section 310-1, which accommodates the rotary drive 450, and a second housing section 310-2 formed integrally with it. This second housing section has a smaller inner diameter than the first housing section 310-1 and is designed to accommodate the expansion drive 550.

[0068] The rotary drive 450 is arranged in an interchangeable first cartridge 400 and is mounted inside the substantially rotationally symmetrical cartridge case 410 of the first cartridge 400. The expansion drive 550 is arranged in a second cartridge 500 and is mounted inside the cartridge housing 510 of the second cartridge.

[0069] The first cartridge 400 can be inserted into the first housing section 310-1 from below. Independently, the second cartridge 500, with its expansion drive, can be inserted into the second housing section 310-2 from above. The expansion drive is coupled to an axially movable feed rod 460, which, during assembly of the spindle unit, is inserted into an inner through-bore of the spindle shaft 152 and, during operation of the honing machine, acts on an axially displaceable expansion cone located inside the honing tool.

[0070] Fig. Figure 6 shows a configuration in which the first cartridge 400 (with rotary drive 450) is installed ready for operation in the spindle unit housing 310, while the second cartridge 500 with the expansion drive 550 has been removed upwards. Fig. Figure 7 shows a configuration in which the second cartridge 500 with expansion drive 550 is inserted into its associated second housing section 310-2, while the first cartridge 400 with rotary drive 450 is removed downwards from the spindle unit housing.

[0071] The overview of Fig. 6 and Fig. Figure 7 shows that the removal or installation of the two cartridges on opposite sides is possible without requiring much installation space on the sides, since to remove or install the second cartridge 500, the slide 165, which can be moved on the base carrier 160, can be moved downwards, while to remove or install the first cartridge 400, the slide 165 with the spindle unit housing 310 can be moved upwards, so that sufficient clearance remains downwards for removing the first cartridge 400 without fear of a collision with the transport system or workpiece holding devices.

[0072] The one-piece spindle unit housing 310, which can be made, for example, of a torsionally rigid aluminum alloy or of a fiber composite material, serves as a mechanical reference for the mutual coaxial alignment of the two cartridges 400, 500 and the components contained therein, as well as a mechanical reference for establishing the correct alignment of these components of the spindle unit 300 with respect to the linear guide system of the lifting drive.

[0073] To ensure that each cartridge is installed in the correct orientation and axial position relative to the corresponding housing section of the spindle unit housing, corresponding mating surfaces are formed on the outer sides of the respective cartridges and the inner sides of the corresponding housing sections. Fig. Figure 7 clearly shows the centering mating surfaces of the first housing section 310-1 for receiving the first cartridge 400. Directly adjacent to the lower end face 315 of the spindle unit housing 310, a rotationally symmetrical lower mating surface 312 is formed on the inside of the same. A rotationally symmetrical upper mating surface 313 is formed at a distance above this, i.e., inside the first housing section 310-1.

[0074] The cartridge housing 410 of the first cartridge 400 has an outwardly projecting flange 415 in its lower third. Its upward-facing flange surface serves as an axial stop surface for abutting the end face 315 of the spindle unit housing, thus defining the axial position of the installed cartridge. Directly above the flange 415 is a wide, rotationally symmetrical mating surface 416, which fits the mating surface 312. A further mating surface 417, which fits the upper mating surface 313, is located at a distance above this. The inner fit between the mating surfaces 313 and 417 has a smaller diameter than the outer fit with the mating surfaces 416 and 312 near the flange 415. This ensures that during assembly, the mating surface only engages when the first cartridge 400 is almost completely inserted into the spindle unit housing.the respective mating surfaces of the associated housing section come into contact with each other and not already at the beginning of the insertion into the spindle unit housing.

[0075] A corresponding solution is also provided for the installation of the second cartridge 500 in the second housing section 310-2. There, too, are two spaced-apart pairs of mating surfaces, as well as a stop surface 515 on the widened head of the second cartridge 500. This stop surface abuts the upper end face 316 of the spindle unit housing 310 when the second cartridge 500 is axially inserted, thereby determining the axial position of the second cartridge 500 within the spindle unit housing. Thus, the correct alignment and axial position of the cartridges are established without any further adjustments once the cartridges have been inserted during assembly on the spindle unit housing.

[0076] A particular challenge lies in providing suitable electrical and fluidic connections for the components installed in the first cartridge 400 of the spindle unit 300. While the components of the second cartridge 500, which houses the expansion drive 550, can be contacted relatively easily directly from above via suitable connections, contacting the components provided in the first cartridge 400 (for example, the rotary drive) from below, i.e., from the side to which the honing tool is coupled, is not possible or only possible with limitations.

[0077] In this embodiment, connection problems for the internal components of the first cartridge 400 are solved by attaching connecting elements of suitable plug connectors to the top of the first cartridge 400, i.e., to the inside facing the second cartridge 500. These interact with corresponding connecting elements of a plug connector on a housing section 318 of the spindle unit housing 310 at the stepped transition from the larger diameter in the first housing section 310-1 to the smaller diameter in the second housing section 310-2.

[0078] In the exemplary embodiment of the Fig. Figure 8 provides self-sealing male connector components of fluid connection elements 470 for the introduction or discharge of liquid or gaseous fluids. Two of the fluid connectors serve for the supply and discharge of coolant for cooling the components arranged within the first cartridge 400, in particular the rotary drive. These connectors are connected to coolant channels 472, which run inside the wall of the cartridge housing 410 of the first cartridge and are only indicated here by dashed lines. Coolant channels can, for example, run helically within the cartridge housing. It is also possible to construct a channel network with partially axially oriented coolant channel sections and cross connections. Two further fluid connection elements can serve for the supply and discharge of coolant to and from the honing tool. Gaseous fluids can also be connected.For example, a connection may be provided to direct sealing air through the cartridge housing 410 of the first cartridge 400 to an outlet on the tool side of the first cartridge.

[0079] The electrical plug contacts 475 supply the rotary drive 450 with electrical power and transmit information from the rotary drive, for example, from temperature sensors. The electrical connections 480 are used for signal transmission from encoders installed in the first cartridge 400, for example, a rotary encoder of the rotary drive, for controlling the honing machine. The rotary encoder can consist of a static and a rotating part, with the static part functioning as a measuring head 485.

[0080] The corresponding sockets are located on the downward-facing side of housing section 318 at the stepped transition between the larger inner diameter of the first housing section 310-1 and the smaller inner diameter of the second housing section 310-2. The electrical and fluidic connections are automatically established in the final stage of insertion when the first cartridge 400 is inserted into the corresponding first housing section 310-1 in the correct rotational position. A suitable structure is provided to ensure that the first cartridge can only be inserted in a single rotational position and pushed in to the stop.

[0081] Further special features of the machine concept of the exemplary embodiment will now be discussed in connection with the Fig. Sections 9A to 9D are explained. The honing machine can be used to hone workpieces of very different heights and bore lengths without requiring any retooling. Fig. 9A and Fig. Figure 9B shows the machining of a workpiece W1, whose workpiece height corresponds to the maximum height WHO of a workpiece height range considered during the design. The honing machine can therefore machine workpieces up to this workpiece height.

[0082] The Fig. 9C and Fig. Figure 9D shows the machining of workpieces W2, which have a lower workpiece height and only a relatively short bore to be machined.

[0083] Accordingly, a relatively long honing tool 190-1 is required for machining the tall workpiece W1, while a relatively short honing tool 190-2 can be used for machining the short bore in the relatively flat workpiece W2, which enables low concentricity errors and therefore high machining quality.

[0084] When designing the honing unit 130, particular attention is paid to an optimal axial mounting position of the base support 160 or the slide box 160 on the support structure 120. The base support 160 is attached to the support structure 120 in such a way that an end 166 closest to the workpiece, i.e., the lower edge 166 of the slide box or the base support 160, is located at a distance above the upper limit WHO of the workpiece height range facing the spindle unit.

[0085] This allows even the tallest workpieces W1 to move below the base support 160 without collision when the rotary table or its table top 184 is rotated around the rotary table axis 185, provided the spindle unit 150 has been retracted sufficiently far upwards. Fig. Figure 9A shows a situation in which the spindle unit 150 has moved to its upper end position. In this example, it is designed such that even when using the longest honing tool 190-1, its workpiece-facing tip extends at most to the level of the lower edge 166 of the base carrier (shown with a dashed line), but no further towards the workpiece. This ensures, on the one hand, free transport of the workpieces when the spindle unit is retracted ( Fig. 9A), on the other hand, the stroke length of the linear movement of the spindle unit is so large that the long honing tool 190-1 can machine the bore over its entire length with an oscillating stroke when the spindle unit is lowered. Fig. Figure 9B shows the spindle unit at its lower reversal point of the oscillating stroke movement, close to the workpiece.

[0086] It is important here that the spindle unit 150 can also move further downwards towards the workpiece if required, as can be seen from the following: Fig. 9D will be explained later.

[0087] Based on Fig. As can be seen in Figure 9C, the workpiece-facing end or the lower edge 166 of the base carrier is arranged far above the movement path of the relatively flat workpieces W2, so that the workpieces can be transported around the rotary table axis 185 to their respective machining position below the spindle unit without collision with the base carrier.

[0088] When using a short honing tool 190-2 to machine the short bore of a flat workpiece, the spindle unit 150 must be moved relatively far downwards or in the direction of the workpieces. Fig. Figure 9D shows a position of the spindle unit close to the lower reversal point of the oscillation movement of the honing tool 190-2 in the bore of the flat workpiece W2. In this illustration, it is clearly visible that in this workpiece-close position of the stroke movement of the spindle unit 150, the tool-side end 153 of the spindle shaft 152, i.e., the spindle nose 153 with the tool-holding device, is moved downwards beyond the lower end 166 of the base carrier and is thus closer to the workpiece height area than the workpiece-close end 166 of the base carrier. In the working position of Fig. Figure 9D also clearly shows that the tool-side end 153 of the spindle shaft projects downwards, i.e., towards the workpieces, beyond the workpiece-side end of the slide plate 165 towards the workpiece side. The projection 167, i.e., the length by which the spindle nose 153 projects beyond the workpiece-side end of the base support 160, can be, for example, 10% or more, or 25% or more, of the total length of the spindle unit between the spindle nose and the upper end of the expansion device.

[0089] Furthermore, the spindle unit 150 is so short in the axial direction, i.e. parallel to the spindle axis, due to the use of electric direct drives for the rotary drive and the expansion drive, that even in the stroke position furthest from the workpiece ( Fig. 9A) the upper end of the spindle unit 150 does not extend beyond the upper end of the base support 160.

[0090] Thus, the machine roof 105 can be mounted directly above the upper end of the base support 160, making it possible to create a compact enclosure for the honing machine, even in the vertical direction.

[0091] Investigations by the inventors into favorable dimensioning ratios have shown that for many practically relevant applications and workpieces, the workpiece height range can be between 250 mm and 500 mm, particularly between 250 mm and 400 mm. The upper limit of the workpiece height range can therefore be, for example, 250 mm to 500 mm above a reference plane, where the reference plane is the plane on which the workpiece holding devices are mounted (in this example, the top of the table). The lower edge 166 of the base support can be one or a few mm above this upper limit. Favorable stroke lengths can be, for example, in the range of 450 mm to 700 mm, particularly between 500 mm and 650 mm. Favorable stroke positions can be, for example, in the range of 150 mm to 900 mm, particularly between 180 mm and 850 mm (also with reference to the aforementioned reference plane). Favorable lengths of the base support can be, for example,The length of the spindle unit is typically in the range of 1000 mm to 1500 mm, particularly in the range of 1100 mm to 1400 mm. Favorable axial lengths of the spindle unit (measured from the spindle nose to the top of the spindle unit housing) can be, for example, in the range of 500 mm to 900 mm, particularly in the range of 600 mm to 800 mm. Typical tool lengths can range, for example, from 100 mm to 150 mm (for shorter honing tools) up to 350 mm to 600 mm (for longer honing tools).

[0092] Considering the constructively possible projection 167 of the spindle nose beyond the lower edge 166 of the base support, this can, for example, be in the range of 20% to 40% of the stroke length, and particularly in the range of 25% to 35% of the stroke length. The upper limit of the workpiece height range can, for example, be from 50% to 75% of the stroke length, and particularly from 60% to 70%. The stroke length can, for example, be in the range of 70% to 90% of the length of the spindle unit. Deviations from these dimensions and dimensional ratios are, of course, possible and may be advantageous in special cases.

Claims

[1] Honing machine (100) for honing a bore in a workpiece, comprising: a machine-resistant support structure (120); at least one honing unit (130) mounted on the support structure (120), which has a spindle unit (150) in which a spindle shaft (152) is rotatably mounted, wherein the spindle shaft (152) is rotatable about a spindle axis (155) by means of a rotary drive (450) and has a device for attaching an expandable honing tool at a tool-side end (153), a lifting drive to generate a lifting movement of the spindle unit (150); a widening drive (550) for widening the honing tool, wherein the widening drive (550) is coupled to an adjustment rod (460) running inside the spindle shaft (152); wherein the spindle unit (150) has a spindle unit housing (310) which has a first housing section (310-1) for receiving the rotary drive (450) and a second housing section (310-2) for receiving the expansion drive (550), characterized by , that the rotary drive (450) is contained in an interchangeable first cartridge (400) and the expansion drive (550) is contained in a second cartridge (500) that can be interchanged independently of the first cartridge (400), wherein the first cartridge (400) can be inserted into the first housing section (310-1) and the second cartridge (500) can be inserted into the second housing section (310-2). [2] Honing machine (100) according to claim 1, characterized by , that the spindle unit housing (310) is designed as a monocoque housing in which the first housing section (310-1) is formed integrally with the second housing section (310-2). [3] Honing machine (100) according to claim 1 or 2, characterized by, that the first cartridge (400) and the second cartridge (500) can be inserted into the spindle unit housing (310) from opposite sides. [4] Honing machine (100) according to any one of the preceding claims, characterized by , that at least one first mating surface (312, 313) is formed on an inner side of the first housing section (310-1), which in contact with at least one corresponding first mating surface (416, 417) on the first cartridge (400) causes an alignment of the first cartridge (400) in the first housing section (310-1) and / or that at least one second mating surface is formed on an inner side of the second housing section (310-2), which in contact with at least one corresponding second mating surface on the second cartridge (500) causes an alignment of the second cartridge (500) in the second housing section (310-2). [5] Honing machine (100) according to any one of the preceding claims, characterized by, that axial stop surfaces (315, 316) are formed on the spindle unit housing (310) to specify an axial position of the first cartridge (400) in the first housing section (310-1) and the second cartridge (500) in the second housing section (310-2). [6] Honing machine (100) according to any one of the preceding claims, characterized by , that corresponding connecting elements (470, 475, 480) of at least one plug connection for the transmission of fluid, electrical power and / or electrical signals are arranged on the side of the first cartridge (400) facing the second cartridge (500) and on the side of a housing section of the spindle unit housing (310) facing the first cartridge (400). [7] Honing machine (100) according to any one of the preceding claims, characterized by , that the expansion drive (550) has a torque motor. [8] Honing machine (100) according to any one of the preceding claims, characterized by, that fluid channels (472) for conveying fluid, in particular cooling fluid for the rotary drive, are formed in a cartridge housing (410) of the first cartridge (400).

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