Device for mounting a plug in a hollow shaft

Abstract

Device (1) for mounting a plug (2) in a hollow shaft (3), - with a holding device (4) for holding the plug (2) to be installed, - with a joining device (5) for sliding the hollow shaft (3) onto the plug (2) held in the holding device (4), - wherein the holding device (4) is radially adjustable to an axis (6) of the hollow shaft (3) in order to compensate for an axis misalignment between the axis (6) of the hollow shaft (3) and an axis (7) of the plug (2), - wherein the joining device (5) is tiltable in order to compensate for an inclination of the axis (6) of the hollow shaft (3) and the axis (7) of the plug (2), characterized by - that the holding device (4) has a floatingly mounted plate (8) on which the plug (2) to be mounted stands, wherein the plate (8) is adjustable in the radial direction (9) relative to the hollow shaft (3) via an air cushion or a ball bearing (10), - that the holding device (4) has a base plate (11), between which and the floatingly mounted plate (8) the air cushion or the ball bearing (10) is arranged, - that the holding device (4) has a centering pin (12) which engages through the base plate (11) and the floatingly mounted plate (8) and centers the latter with play, or - that the holding device (4) has a floatingly mounted plate (8) on which the plug (2) to be mounted stands, wherein the plate (8) is adjustable in the radial direction (9) relative to the hollow shaft (3) via an air cushion or a ball bearing (10), - that the holding device (4) has a collar (13) which encompasses the ball bearing (10) and together with the floatingly mounted plate (8) forms a receptacle for the plug (2).

Description

[0001] The present invention relates to a device for mounting a plug in a hollow shaft. The invention also relates to a method for mounting a plug in a hollow shaft using such a device.

[0002] From DE 195 31 832 C2 a device for determining and controlled compensation of position and / or orientation errors when joining components by longitudinal pressing is known.

[0003] From DE 10 2008 064 194 A1, a device for positioning at least one functional element having a recess for a hollow shaft in a predetermined angular position on the hollow shaft is known, wherein the device has a receptacle intended for a functional element.

[0004] From DE 10 2007 056 638 A1, a further device for assembling a composite consisting of at least one hollow shaft carrying functional elements and a housing supporting these elements in undivided bearings is known. The housing has positioning devices that, prior to assembly, hold the functional elements in a predetermined phase position within the housing such that the at least one hollow shaft can be inserted through the housing bearings and openings in the functional elements. The positioning device is provided with recesses for the functional elements, which have a stop that supports the functional element against the assembly direction of the hollow shaft. The recess of the positioning device has a partial contour of the contour of the functional elements as a negative profile, so that the functional elements can be held in a phase position corresponding to their subsequent assembly position. This is intended to achieve particularly phase-accurate positioning.

[0005] From DE 10 2009 060 350 A1, a device for mounting a hollow shaft carrying functional elements is known, wherein the device comprises a machine platform on which a plurality of positioning discs are arranged for the aligned, dimensionally correct positioning of the functional elements such that a hollow shaft can be inserted. The positioning discs are reversibly fixed on a frame, which in turn is reversibly fixed on the machine platform. The provision of several frames is intended to enable a rapid changeover in a production process.

[0006] From DE 10 2011 106 981 A1, a device for producing a joining connection between at least one component having a bore and a hollow shaft is known, wherein the device has a joining unit with a first gripper for gripping the hollow shaft and a second gripper for gripping the component in a position-oriented manner. The hollow shaft is clamped centrally at one end in a rotatably mounted clamping device and is centered at the other end with a centering tip, whereby the component is heated to a desired temperature and the bore expands to an interference with the diameter of the hollow shaft. This is intended, in particular, to create a device with which a joining process can be optimized.

[0007] From EP 2 777 868 B1, a further device for positioning at least one functional element having a hub for a hollow shaft on the hollow shaft is known.

[0008] When pressing plugs into hollow shafts, varying, and especially increased, joining forces can occur due to manufacturing tolerance-related misalignments or axial misalignments between a plug axis and a hollow shaft axis. In particular, so-called galling cannot be ruled out, where the plug digs into the hollow shaft material due to misalignment. Besides damaging the plug and / or the hollow shaft, misalignment of the plug or axial misalignment between the plug and hollow shaft can also negatively affect the concentricity and axial runout of the plug relative to the outer diameter of the hollow shaft on the finished part. This has a detrimental effect. Therefore, surfaces with tight tolerance requirements regarding concentricity and axial runout must be subsequently...After the plug is inserted into the hollow shaft, it requires extensive machining, especially reworking, which leads to significant additional costs.

[0009] The present invention therefore deals with the problem of providing an improved or at least an alternative embodiment for a device of the generic type, which in particular overcomes the disadvantages known from the prior art.

[0010] This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject matter of the dependent claims.

[0011] The present invention is based on the general concept of using, for the first time, a device for inserting a plug into a hollow shaft that is capable of compensating for both axial misalignment and skew between the plug and the hollow shaft, thereby enabling the insertion or assembly of the plug into the hollow shaft with high concentricity and axial runout. The device according to the invention comprises a holding device for holding the plug to be installed and an insertion device for sliding the hollow shaft onto the plug held in the holding device. According to the invention, the holding device is radially adjustable relative to the axis of the hollow shaft, so that the plug held in the holding device is also radially adjustable relative to the axis of the hollow shaft or to its own axis, and can thus compensate for axial misalignment between the hollow shaft and the plug.In contrast, the joining device is tiltable, which compensates for any misalignment of the hollow shaft and thus any angular deviation between the axis of the hollow shaft and the axis of the plug. Using the device according to the invention, it is therefore possible to compensate for both misalignment of the axes of the hollow shaft and the plug, as well as any axial misalignment, thereby achieving extremely high joining quality. In particular, the device according to the invention eliminates the need for potentially necessary, complex, and expensive post-processing of radial or axial runout due to tight tolerance requirements.

[0012] According to the invention, the holding device comprises a floatingly mounted plate on which the plug to be installed rests. The plate is adjustable in the radial direction relative to the hollow shaft via an air cushion or a ball bearing. Thus, when the plug is positioned in the holding device, it rests on the floatingly mounted plate, which is able to compensate for any axial misalignment through radial movements. The radial adjustability is, of course, limited to a maximum of a few millimeters and serves solely to compensate for any misalignments or axial misalignments between the axis of the hollow shaft and the axis of the plug before or during assembly.

[0013] In a first embodiment according to the invention, the holding device has a base plate between which and the floatingly mounted plate the air cushion or the ball bearing is arranged. The base plate, the floatingly mounted plate, and the balls or air space arranged between them thus constitute the actual radial bearing and enable the compensation of any axial misalignment that may be present.

[0014] In the first embodiment according to the invention, the holding device has a centering pin that engages through the base plate and the floating plate, centering the latter with some play. The opening in the floating plate is thus slightly larger in its inner diameter than the outer diameter of the centering pin, so that the centering pin only roughly centers the floating plate, but allows a certain amount of radial movement to compensate for any possible axial misalignment between the plug and the hollow shaft. Furthermore, the centering pin has the function of recentering the floating plate after each joining operation, so that its radial movement in all directions is possible during the subsequent joining operation.

[0015] In a second embodiment according to the invention, the holding device has a floatingly mounted plate on which the plug to be mounted rests. The plate is adjustable in the radial direction relative to the hollow shaft via an air cushion or a ball bearing. The holding device has a collar that encompasses the ball bearing and, together with the floatingly mounted plate, forms a receptacle for the plug. Such a collar thus forms a surrounding edge for the plug to be received in the holding device. The plug is arranged with radial play in the collar and rests on the floatingly mounted plate. The collar, which in this case represents a surround for the plug, thus serves solely to securely receive the plug.

[0016] Advantageously, the joining device is arranged above the holding device. Ideally, the holding device is positioned below, with the plug resting on the floating plate. The hollow shaft is then positioned essentially vertically above this, so that the hollow shaft and the joining device, both located above the holding device, are arranged one above the other. By lowering the joining device, the hollow shaft is pressed onto the plug held in the holding device. The tilting of the joining device and the radial adjustability of the holding device compensate for any axial misalignment between the hollow shaft and the plug, as well as any tilting of the hollow shaft relative to the plug. This allows for extremely precise installation of the plug in the hollow shaft, meeting even the highest requirements for concentricity and axial runout.

[0017] The joining device can be tilted by up to 7.5°. A deviation greater than 7.5° is not usually expected, so that the specified number of degrees can compensate for all angles of misalignment of the hollow shaft relative to the plug.

[0018] The present invention is further based on the general concept of providing a method for inserting a plug into a hollow shaft using the previously described device, in which the plug is first arranged in the holding device. Here, the plug is positioned on the floatingly mounted plate of the holding device within the collar. Subsequently, the hollow shaft is positioned substantially vertically above the plug, with the joining device pressing down on the hollow shaft from above and sliding it over the plug. Simultaneously, the holding device and the plug are adjusted radially relative to the axis if there is an axial misalignment between an axis of the hollow shaft and an axis of the plug, and the joining device is tilted if there is an inclination of the axes of the hollow shaft and the plug. The hollow shaft can be connected to the joining device.Using the method according to the invention, the plug can thus be positioned extremely precisely, especially with regard to its position and orientation in the hollow shaft, thereby meeting the highest requirements for the concentricity and flatness of the joined hollow shaft without having to, for example, perform elaborate and costly rework.

[0019] The joining of the hollow shaft to the plug can be thermally supported, for example, by cooling the plug and / or heating the hollow shaft, although a pure press fit is of course also conceivable.

[0020] Further important features and advantages of the invention will become apparent from the dependent claims, the drawings and the associated description of the figures based on the drawings.

[0021] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0022] Preferred embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals refer to identical or similar or functionally identical components.

[0023] Each of these shows, schematically, Fig. 1 a device according to the invention, Fig. 2 a detailed representation of a holding device of the device according to the invention.

[0024] According to the Fig. 1 A device 1 according to the invention for mounting a plug 2 in a hollow shaft 3 has a holding device 4 (see also Fig. 2) and a joining device 5. The holding device 4 holds the plug 2 to be installed. The joining device 5 pushes the hollow shaft 3 onto the plug 2. According to the invention, the holding device 4 is radially adjustable with respect to the hollow shaft 3 in order to compensate, for example, for an axial misalignment between the hollow shaft 3 and the plug 2. The joining device 5 is also tiltable, for example by an angle α of up to 7.5°, in order to compensate for an inclination of the hollow shaft 3.

[0025] For example, consider the Fig. 1, so one can see a wide variety of misalignments between hollow shaft 3 on the one hand and plug 2 on the other.

[0026] In diagram A, for example, the axis 7 of the plug 2 is arranged at an angle to the axis 6 of the hollow shaft 3, which can be compensated for by the tilting or tilting joining device 5. In contrast, in diagram B, there is an axial misalignment between the axis 7 of the plug 2 and the axis 6 of the hollow shaft 3, so that the two axes 6 and 7 run parallel to each other in this case. This can be compensated for by a radial adjustment of the holding device 4 in the radial direction 9. As a result, shortly before the joining process, diagram C is established, in which the axis 6 of the hollow shaft 3 runs coaxially to the axis 7 of the plug 2, so that there is neither an axial misalignment nor an inclination of the two axes 6 and 7, and optimal joining of the plug 2 in the hollow shaft 3 can take place.

[0027] By compensating for any misalignments between hollow shaft 3 and plug 2, extremely tight tolerance requirements regarding concentricity and axial runout can be met without the need for subsequent, complex and therefore expensive reworking of the entire manufactured hollow shaft 3.

[0028] If one examines the holding device 4 more closely, one can see that it is a floatingly mounted plate 8 (cf. Fig. 2) has a base plate 8 on which the plug 2 to be mounted stands, wherein the plate 8 is adjustable in radial direction 9 relative to the hollow shaft 3 via an air cushion or, in the illustrated case, via a ball bearing 10. The holding device 4 also has a base plate 11, between which and the floatingly mounted plate 8 the air cushion or the ball bearing 10, here the individual balls of the ball bearing 10, are arranged.

[0029] Furthermore, the holding device 4 has a centering pin 12 that engages through the base plate 11 and the floating plate 8, centering the latter with play. This has the significant advantage that after each completed joining operation, the floating plate 8 is realigned relative to the centering pin 12, thus allowing radial play in all radial directions 9 during a subsequent joining operation. The holding device 4 also has a collar 13 that encompasses the ball bearing 10 and the floating plate 8, and simultaneously forms a surround for the plug 2 held in the holding device 4.

[0030] In general, the joining or sliding of the hollow shaft 3 onto the plug 2 is carried out using the device 1 according to the invention as follows: First, the plug 2 is positioned in the holding device 4, i.e., placed on its floatingly mounted plate 8. Then, the hollow shaft 3 is positioned essentially vertically above the plug 2, and subsequently, the joining device 5 presses down on the hollow shaft 3 from above. this is pushed over the plug 2. Before or during this process, the holding device 4, or its floatingly mounted plate 8, and above it the plug 2, adjust radially, i.e., in the radial direction 9, relative to the axis 6 of the hollow shaft 3, provided there is an axial misalignment between the axis 6 of the hollow shaft 3 and the axis 7 of the plug 2. Also before or during the joining process, the joining device 5, and thus the hollow shaft 3, tilts if the hollow shaft 3 is inclined, i.e., if the axes 6 and 7 are not coaxially arranged, i.e., identical. Using the method according to the invention, it is possible to align the hollow shaft 3 relative to the plug 2, or the plug 2 relative to the hollow shaft 3, in such a way that extremely precise joining of the plug 2 in the hollow shaft 3 is possible, meeting the highest requirements for concentricity and axial runout.

[0031] The joining process can be achieved by a press fit, i.e., the hollow shaft 3 is pressed onto the equally cold plug 2 while cold. Naturally, this joining process can be further enhanced by a thermal joining process, for which the plug 2 is cooled and / or the hollow shaft 3 is heated.

Claims

[1] Device (1) for mounting a plug (2) in a hollow shaft (3), - with a holding device (4) for holding the plug (2) to be installed, - with a joining device (5) for sliding the hollow shaft (3) onto the plug (2) held in the holding device (4), - wherein the holding device (4) is radially adjustable to an axis (6) of the hollow shaft (3) in order to compensate for an axis misalignment between the axis (6) of the hollow shaft (3) and an axis (7) of the plug (2), - wherein the joining device (5) is tiltable in order to compensate for an inclination of the axis (6) of the hollow shaft (3) and the axis (7) of the plug (2), characterized by , - that the holding device (4) has a floatingly mounted plate (8) on which the plug (2) to be mounted stands, wherein the plate (8) is adjustable in the radial direction (9) relative to the hollow shaft (3) via an air cushion or a ball bearing (10), - that the holding device (4) has a base plate (11), between which and the floatingly mounted plate (8) the air cushion or the ball bearing (10) is arranged, - that the holding device (4) has a centering pin (12) which engages through the base plate (11) and the floatingly mounted plate (8) and centers the latter with play, or - that the holding device (4) has a floatingly mounted plate (8) on which the plug (2) to be mounted stands, wherein the plate (8) is adjustable in the radial direction (9) relative to the hollow shaft (3) via an air cushion or a ball bearing (10), - that the holding device (4) has a collar (13) which encompasses the ball bearing (10) and together with the floatingly mounted plate (8) forms a receptacle for the plug (2). [2] Device according to claim 1, second alternative, characterized by , that the holding device (4) has a base plate (11), between which and the floatingly mounted plate (8) the air cushion or the ball bearing (10) is arranged. [3] Device according to claim 1, second alternative, or according to claim 2, characterized by , that the holding device (4) has a centering pin (12) which engages through the base plate (11) and the floating plate (8) and centers the latter with play. [4] Device according to any one of the preceding claims, characterized by , that the joining device (5) is arranged above the holding device (4). [5] Device according to any one of the preceding claims, characterized by, that the joining device (5) can be tilted by up to 7.5°. [6] Method for inserting a plug (2) into a hollow shaft (3) using a device (1) according to one of the preceding claims, wherein - the plug (2) is arranged in the holding device (4), - the hollow shaft (3) is positioned essentially vertically above the plug (2), - the joining device (5) presses down onto the hollow shaft (3) and pushes it over the plug (2) and - the holding device (4) with the plug (2) is adjusted radially to the hollow shaft (3) if there is an axial offset between the axes (6, 7) of the hollow shaft (3) and the plug (2), and the joining device (5) is inclined if there is an inclination of the axis (6) of the hollow shaft (3) and the axis (7) of the plug (2).

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