The object of the invention is to disclose a device according to the
preamble of Claim 1, which, with an
4 easy-to-assemble structure, in particular with respect to the arrangement of the coolant supply, allows optimum grinding results to be obtained at the same time as a high cutting rate, while overcoming the high temperature stresses which occur.
The object set is attained according to the invention by the features of the characterizing part of Claim 1.
A device is produced which is easy to assemble and maintain. After the spacer rings and one or more grinding discs have been positioned axially in the required manner, longitudinal grooves are covered on the outside and in this way the essentially axial duct channels are formed, which are each connected to a "bundle" of radial cooling ducts in the grinding discs. Pressing the disc carrier axially onto the machine shaft - for example in surface receiving means mutually corresponding in a conical manner - forms at the same time the annular seal corresponding in the manner of a web, and therefore a multiple coolant supply by way of the part of the annular seal fixed to the housing. It is possible to meet a relatively high demand for coolant which can be adapted to a plurality of grinding discs and which, in addition, takes into consideration the two "temperature hearths" (grinding roller / component machining) noted above.
According to the invention an optimum cooling of at least one grinding disc completely over the periphery thereof can be performed by way of the cooling ducts arranged accordingly at a distance from one another. The cooling ducts are arranged in such a way that they incorporate the outer peripheral region of the disc subjected as a whole to high temperature in the cooling of the component. The number and cross-sections of the cooling ducts can be adapted to the requirements of cooling and the cooling liquid. By the relative mutual spacing of the cooling ducts, and therefore also of the respective discharge openings - per grinding surface in the axial and peripheral directions - the respec tive effective grinding surface together with the opposite face to be machined can be flushed uniformly or in part with lubricating cooling liquid, and to a more pronounced extent if necessary.
The device according to the invention is optimally suited for grinding turbine-engine components, even of highly complicated design, for example blades and their base plates or top plates, sealing rings or carrier and support rings. In this case, locally differing designs and profiling of the components can be based on profiles of grinding discs adapted thereto in a single, or 6 preferably at the same time a multiple, arrangement of the discs.
Advantageous embodiments of the invention may be seen in the features of Claims 2 to 13.
The invention is explained in greater detail by way of example with reference to the drawings, in which Fig. 1 is an illustration, partly in side view and partly in a cut-away axial section, of the coordination and arrangement on the machine and of the essential basic structure of the grinding device; Fig. 2 shows a radially upper portion of the device cut-away locally and based on the axial section of Fig. 1 - in particular illustrating details of the annular seal as well as associated connexions to the duct channels and to the cooling ducts connected thereto; Fig. 3 shows a lower portion of the device - cut-away locally and based on the axial section of Fig. 1 - in which in particular the cooling liquid supply of the annular seal from the radially outer part on the housing as well as a 7 line-connecting member are illustrated; Fig. 4 is a local cross-section through the disc with a plan view of the inner peripheral face - ending in the direction of the axis of the disc - of the said portion of the disc with the associated arrangement of the cooling ducts on the inflow side; Fig. 5 is a plan view of the portion of the disc as shown in Fig. 4, illustrating the arrangement of the cooling ducts (discharge openings) on the outflow side on the outer periphery; Fig. 6 is a plan view of a portion - shown cut away at the outside on both sides relative to the axis of the disc or machine - of a grinding disc as shown in Fig. 2 and in an arrangement of the cooling ducts modified with respect to Figs. 4 and 5; Fig. 7 shows a diamond grinding roller as an axial section and, relative to an annular intermediate member cut away on the outside, in a side view, and in the machining position relative to a portion of the disc radially on the outside, and 8 Fig. 8 shows a radially lower portion - cut away locally - of the grinding disc as shown in Fig. 7 in the machining position at the tip of a component, in particular a blade cover strip.
Fig. 1 shows the essential basic features of the grinding device. Two grinding discs 2, 3 for example are mounted on a drive shaft 1, the grinding discs 2, 3 being produced in particular from corundum and being coolable by a cooling liquid with continuous re-grinding of the grinding surfaces thereof during the machining of the component. The cooling liquid may be cooling water or a lubricating cooling liquid, for example a cooling oil. The "corundum" material may be a so-called Itelectrocorundum (Al 2 0 3)11 or a sintered ceramic material, for example sintered corundum (SG). The grinding discs 2, 3 are annular and have cooling ducts K, K' which extend substantially radially from the inner to the outer wall periphery of the respective disc and are distributed over the periphery of the disc. The grinding discs 2, 3 are secured in a rotationally fixed manner between axially detachable spacer rings 4, 5, 6 on a drum-shaped disc carrier 7 which is mounted axially detachably on the machine shaft 1. A plurality of cooling ducts K, K' in the grinding discs 2, 3 are each connected radially an the inside to duct channels 8 for the supply of cooling liquid. The duct channels 8 are 9 formed between longitudinal grooves 9 on the outer periphery of the disc carrier 7 and inner peripheral faces of the grinding discs 2, 3 and the spacer rings 4, 5, 6. The duct channels 8 are attached to an axial annular seal 10 corresponding in the manner of a web (v.i. also Figs. 2 and 3) of which a stationary part is detachably connected to a housing portion 11 of the machine coaxial with the shaft and comprises a plurality of supply ducts 12 distributed over the periphery for the cooling liquid, namely in the form of continuous radial openings which are each connected to a screwed-on duct connexion L (Fig. 3).
The two grinding discs 2, 3 can be fixed axially by the spacer rings 4, 5, 6 on a radial peripheral flange 13 of the disc carrier 7. The rotating part (annular plate 16 - Figs. 2 and 3) of the annular seal 10 can be fixed axially detachably on the peripheral flange 13.
In principle the annular seal 10 is formed between axial webs S, S, overlapping radially at a distance (Figs. 2 and 3) on the rotating and stationary sealing part.
The duct channels 8 of the grinding device extending substantially axially (Fig. 1) are arranged distributed over the periphery at uniform distances, each duct channel 8 being connected to a plurality of cooling ducts K, K' in the two grinding discs 2, 3 and each being connected by way of at least one axial opening 14 (Fig. 2) in the radial peripheral flange 13 to the annular chamber 15 of the annular seal 10.
The rotating part of the annular seal 10 is formed with the associated axial webs S (Fig. 2) on an annular plate 16 which is screwed axially (position Sr) to the d rum. -shaped disc carrier 17 at the level of the laterally outer end face of the peripheral flange 13 and which has openings 17 corresponding to the axial openings 14 of the peripheral flange 13.
The stationary part of the annular seal 10 (Fig. 1) comprises an essentially radially outer and a radially inner annular insert part 18, 19 (Figs. 2 and 3). The radially inner insert part 19 is screwed to the front end of the machine housing 11 (position Sri - Fig. 3). The radially outer insert part 18 forms the radial supply ducts 12 for the cooling liquid into the annular seal 10 (Fig. 3) and is screwed axially to the radially inner insert part 19 (Fig. 2), namely in accordance with position Sr-.
As shown in Fig. 2 in particular, the annular chamber 15 of the annular seal 10 is formed essentially 11 between two axial webs S' - arranged one above the other at a distance radially - of a substantially U-shaped ring 20 open on one side. This ring 20 is tied in between opposed peripheral faces of the radially outer and the radially inner annular insert part 18, 19 and is screwed to the latter insert part 19 axially (position SrIll). On the radially outer side, the ring 20 forms fluid connexions of the radial supply ducts 12 to the annular chamber 15 locally (Fig. 3).
As shown in Fig. 1, the two grinding discs 2, 3 and the spacer rings 4, 5, 6 are tied in a rotationally fixed manner by an annular housing cover 21 screwed with the disc carrier 7 axially on the front or screwed onto the said disc carrier 7. Means can be provided for sealing the cooling liquid on or between opposed axial seating faces of the discs and rings or between a ring 4 and the cover 21. Paste-like means, or rubber-elastic sealing washers or the like can be used as the sealing means.
As shown in Fig. 1 and Fig. 8, the cooling ducts K, K' in the respective grinding disc 2, 3 can terminate on the outside in portions of the grinding faces angled relative to one another.
As shown in Figs. 4 and 5, with reference to the 12 example of a grinding disc 3, the cooling ducts K, K' are arranged with the discharge openings thereof in two rows spaced uniformly axially and are distributed uniformly over the periphery.
All the cooling ducts K, K' can be formed by bores.
A plurality of rows of cooling ducts can be arranged with the discharge openings thereof in a spaced sequence changing periodically on the periphery of the disc. As further shown in Fig. 6, the radially outer centres of the openings of the cooling ducts K', M' can coincide with straight generatrices M which are constantly uniformly inclined with respect to the disc axis or longitudinal axis L of the device and are spaced uniformly in the peripheral direction. Inter alia, relatively large quantities of cooling liquid can be supplied in this way per given face during the grinding process.
Fig. 7 illustrates a diamond grinding roller 22 in a machining position radially on the outside with respect for example to the respective grinding disc 3. The said grinding roller 22 can be connected by way of a connecting or spacer ring-23 to a further grinding roller for the further grinding disc 2 (Fig. 1).
13 In the example of the grinding disc 3, Fig. 8 illustrates a relative machining position with respect to the component B, in this case while surface-machining sealing tips of a blade cover strip. It will be noted that partial sections of the cooling ducts K, radially on the outside extend as far as the surfaces on the tip of the component to be machined.
In addition, in the grinding device according to the in vention it is provided that the cooling liquid, for example cooling water, is supplied by way of respective duct connexions L (Fig. 3) and supply ducts 12 at a pre-determined pressure and furthermore can be removed radially to the outside by way of the cooling ducts K, K' (Figs. 1, 4 and 5) and K', M' (Fig. 6) respectively by the action of the centrifugal force which is present.
14 Claims:
1. A grinding device for machining components, in which at least one grinding disc is mounted on a drive shaft, the grinding disc being coolable by a cooling liquid with continuous re-grinding of the grinding surfaces thereof during machining, wherein - the grinding disc is annular and has cooling ducts extending from the inner to the outer wall periphery of the disc and distributed over the periphery of the disc, - the grinding disc is secured in a rotationally fixed manner between axially detachable spacer rings on a disc carrier mounted axially detachably on the drive shaft, - a plurality of the cooling ducts in the grinding disc are each connected at the radially inner ends thereof to duct channels for the supply of cooling liquid, - the duct channel are formed between longitudinal grooves on the outer periphery of the disc carrier and inner peripheral faces of the grinding disc and of the spacer rings, is the duct channels are connected via an annular seal to supply ducts for the cooling liquid, the annular seal being constructed in the manner of a web between the disc carrier and a housing of the device.
A grinding device according to Claim 1, wherein one or more grinding discs may be fixed axially by the spacer rings on a radial peripheral flange of the disc carrier, the rotating part of the annular seal being fixed axially detachably on the peripheral flange.
A grinding device according to Claim 1 or 2, wherein the annular seal is formed between axially-extending, overlapping and radially-spaced webs on the rotating and stationary sealing parts.
A grinding device according to any one of Claims 1 to 3, wherein the duct channels extend axially of the disc carrier, are distributed uniformly over the periphery thereof, are each connected to a plurality of cooling ducts in the grinding disc and are each connected via at least one axial opening in the radial peripheral flange to an annular chamber of the annular seal.
16 5. A grinding device according to Claim 4, dependent on Claim 2, wherein the rotating part of the annular seal is formed with the associated axial webs on an annular plate screwed axially to disc carrier at the level of the laterally outer end face of the peripheral flange and provided with openings aligned with the axial openings of the peripheral flange.
6. A grinding device according to any one of Claims 1 to 5, wherein the stationary part of the annular seal comprises a substantially radially outer and a radially inner annular insert part, the radially inner insert part being screwed to the front end of the device housing and the radially outer insert part forming radial supply ducts for the cooling liquid into the annular seal and being screwed axially to the radially inner insert part.
7. A grinding device according to any one of Claims 1 to 6, wherein the annular chamber of the annular seal is formed substantially between two axially-extending webs arranged radially spaced one above the other being the less of a substantially U-shaped ring open on one side and bridging opposed peripheral faces of the radially outer and the radially inner annular insert parts, the U-shaped ring being axially screwed to the radially inner 17 annular insert part and on the radially outer side thereof forming fluid connections of the radial supply ducts to the annular chamber.
8. A grinding device according to any one of the preceding claims, wherein one or more annular grinding discs and spacer rings are held in a rotationally fixed manner by an annular housing cover screwed axially and frontally with the disc carrier or on the said disc carrier, means being provided for sealing the cooling liquid on or between opposed axial seating faces of the discs and rings or between a spacer ring and the cover.
9. A grinding device according to any one of the preceding claims, wherein the cooling ducts in the respective grinding discs terminate on the outside in portions of the grinding faces angled relative to one another.
10. A grinding device according to any one of the preceding claims, wherein the discharge openings of the cooling ducts in the grinding disc are uniformly distributed over the periphery thereof in uniformly-spaced axial rows.
11. A grinding device according to any one of the 18 preceding claims, wherein the cooling ducts are formed by bores.
12. A grinding device according to any one of the preceding claims, wherein a plurality of rows of cooling ducts are arranged with the discharge openings thereof in a spaced sequence changing periodically on the periphery of the disc.
13. A grinding device according to any one of the preceding claims, wherein the radially outer centres of the openings of the cooling ducts coincide with straight generatrices constantly uniformly inclined with respect to the disc axis or longitudinal axis of the device and are spaced uniformly in the peripheral direction.
14. A grinding device substantially as herein described with reference to any one of the embodiments shown in the accompanying drawings.