WO1989001844A1

WO1989001844A1 - Drill quill for insertion in a milling spindle

Info

Publication number: WO1989001844A1
Application number: PCT/EP1988/000751
Authority: WO
Inventors: Franz Lechner
Original assignee: Franz Lechner
Priority date: 1987-08-24
Filing date: 1988-08-22
Publication date: 1989-03-09
Also published as: DE3728215C1; EP0378558A1; JPH02504609A

Abstract

A drill quill (2) for insertion in a rigidly mounted milling spindle (12) comprises essentially a drive spindle (4) which can be inserted in a known manner in the milling spindle, a drill spindle (30) rigidly coupled to the drive spindle in the direction of rotation and axially movable with respect to the latter, a housing (22) rotatably mounted on the drive spindle but which can be blocked to prevent rotation with the latter, a feed transmission element (60) which rotates with respect to the drill spindle but is axially stationary with respect to the latter and which is axially movable with respect to the housing but rigidly coupled to the latter in the direction of rotation, and a manually operated feed control element (86) coupled through a gear to the transmission element and mounted in the housing with a transverse physical axis of rotation (84). In order to obtain a feed force which acts coaxially on the drill spindle, the feed transmission element (60) is designed as a sleeve surrounding the drill spindle and is connected in the axial direction at two diametrically opposed positions (102) to chains (98) which are guided by deflection rollers (104) and can be wound on a winding drum (92) mounted in the axis of rotation (84) of the feed control element (86).

Description

Drill quill for insertion in milling spindles

The invention relates to a drilling quill for insertion into milling spindles according to the preamble of claim 1.

Such a drilling quill is known from DE-G 76 18 268 in the form that the feed transmission member as a rack running on one side along the drilling spindle with which a pinion meshes on the physical axis of rotation of the feed drive member. This solution suffers from the fact that the force to be exerted on the drilling spindle acts eccentrically and, due to the meshing of the teeth, partly also sideways, which leads to deformations and distortions or at least to one-sided bearing wear and thereby inaccuracies, and further that the rack protruding outwards from the housing is susceptible to the absorption of dirt and chips.

The object of the invention is to remedy this, i.e. to design a drilling sleeve according to the generic term so that the feed force acts axially and centrally on the drilling sleeve and there are no unevenness on the feed transmission member for receiving dirt and chips.

This object is achieved according to the invention by the characterizing features of claim 1. The subclaims also specify advantageous design options.

The chains acting symmetrically on the relevant sleeve-shaped feed transmission link make it possible to Introduce feed force centrally and axially directed into the drilling spindle, all the more if the feature of claim 6 is additionally used. In addition, the feed transmission member, insofar as it emerges from the housing, can be completely smooth-walled.

Two exemplary embodiments are described in more detail below with reference to the accompanying figures. It shows

1 shows the drilling quill in question together with the immediately adjacent machine parts in two longitudinal half-sections (see line II in FIG. 2) in different parallel planes in a first embodiment, the drilling spindle also being in two differently extended positions appears

Fig. 2 shows the same drilling spindle sleeve cut into a cranked Quer¬, following _^ the line II-II of Fig. 1, except that a top left corner appears in FIG. 1 Board rotated relative to the other parts by 90 appears in approximately,

3 shows the upper section of the drilling sleeve in question, together with the adjacent machine parts, in a somewhat modified embodiment, partially cut away,

Fig. 4 is a top view of the quill from Fig. 3, with a portion on the right side appears broken, and

5 is a detailed view from the plane of the line V-V of FIG. 4th

The drilling sleeve 2 shown in FIGS. 1 and 2 has a drive spindle 4, which has a conventional cone 6 in the relevant tool holder 8, a milling spindle 12 rigidly mounted in a milling head 10 is received. In likewise conventional manner is at the end of the Konus¬ ses 6 a ^'profiled tightening bolt 14 ^ which is held by a screwed shaft 16 in the cone. 6

Following the inside, i.e. In FIG. 1 the lower end of the cone 6, the drive spindle 4 carries a collar 18 on which a housing 22 is rotatably mounted relative to the drive spindle 4 by means of a so-called four-point bearing (a ball bearing which is equally stable in the axial and radial directions) 20 . The four-point bearing 20 is covered on the outside by a profiled sealing ring 23. Beyond the collar 18, the drive spindle 4 continues in a sleeve-shaped section 24. More precisely, it has in its interior a substantially cylindrical coaxial recess 26 which extends as far as the shaft 16 of the tightening bolt 14.

The recess 26, of which at least the part located within the collar 18 and the sleeve-shaped section 24 is finely machined, receives the shaft 28 of a drilling spindle 30, which is longitudinally displaceable therein, however, by an axial groove 32 and by a bore 34 in the drive spindle 4 protruding sliding block 36 is secured against rotation with respect to the drive spindle 4.

At its outer end (in FIG. 1 below), the drill spindle 30 directly carries an essentially conventional drill chuck 38, consisting of a bell 44 mounted on a flange 42 of the drill spindle 30 via a dense succession of balls 40, on which the Cone cap 46 of the drill chuck is screwed on, the jaws 48 mounted therein longitudinally and radially displaceably and one by means of a Left-hand thread in a corresponding coaxial threaded bore 50 of the drilling spindle 30 threaded bolt 52 with a head 54, in which the jaws 48 are mounted in corresponding radial grooves 56. When the cone cap 46 is rotated in the sense of tightening or loosening the drill chuck, the threaded bolt 52 is taken along, that is, screwed in more or less far.

Another comparable clamping device, such as a collet chuck, could of course also take the place of the drill chuck 38.

By means of a further four-point bearing, 58, a sleeve-shaped feed transmission member 60 is rotatable on the bell 44 relative to the drilling spindle 30, but is immovably mounted in the axial direction. This feed transmission member 60, which engages over the sleeve-shaped section 24 of the drive spindle 4, is itself overlapped on the outside by a partially sleeve-shaped section 64 of the housing 22, which in any case ends in a closed ring 62. On the inside, the ring 62 carries a sealing ring 66 which bears against the outer wall of the feed transmission member 60, just as the feed transmission member 60 is sealed outside of the four-point bearing 58 by means of a sealing ring 68 on the bell 44.

At its other end, outside the four-point bearing 20, the housing 22 carries a clamping ring 70, on which a claw 74 is pivotally mounted in a radial plane with respect to the common spindle axis 76 between two lateral extensions 72. The claw 74 is under the action of a spring 78 which tends to press the claw towards the milling head 10 (according to FIG. 1 upwards), where it engages with a fixing pin 80 embedded in the milling head. The clamping ring 70 can on the housing 22 can be held by internal stress, which it receives through an axial slot in connection with an inner cylinder surface made with undersize. Alternatively, it can be designed like a clamp. Another possibility is described below with reference to FIGS. 3 and 4.

The housing 22 also has an eccentric, transverse bulge 82, in which a physical axis of rotation 84 is rotatably mounted by means of a feed drive element in the form of a turnstile 86. On the axis of rotation 84, again rotatably, two sections 88 and 90 of a winding drum 92 are arranged, which are connected to one another by a differential bar 96 as if they were connected to an intermediate drive ring 94 that was keyed to the axis of rotation 84. The differential bar 96 consists of a pin received by corresponding holes, which is able to assume a certain inclined position, at least in the tangential direction, so that one or the other of the two winding drum sections 88 and 90 has a certain advance or lag with respect to the axis of rotation 84 enable.

A chain (drive chain) 98 can be wound onto each of the two winding drum sections 88 and 90 in a single turn, the other end of which engages a lateral projection 100 at the inner end of the sleeve-shaped feed transmission member 60. More precisely, the two relevant points of attack 102 are diametrically opposite on both sides of the feed transmission element. Furthermore, the chains 98 are guided from there exactly parallel to the spindle axis 76 before they each run over a deflection roller 104 mounted in the housing 22 to the winding drum 92.

As can be seen, the feed transmission member 60 and him via the four-point bearing 58, the drilling spindle 30 can be driven out by winding the chains 98 in the sense that the drilling spindle experiences a feed movement with respect to the drive spindle 4 and the milling spindle 12. The section of the feed transmission member 60 emerging from the housing 22, more precisely: the ring 62, is completely smooth on the outside, so that it does not tend to pick up and pull in dirt and chips.

To return the drilling spindle 30, it is suspended from a tension spring (return spring) 106, which is anchored at its other end, in the vicinity of the shaft 16 of the pull bolt 14, in the recess 26 of the drive spindle 4. A substantial part of the spring 106 is received by a corresponding recess 108 in the drilling spindle 30.

In the event that for some reason the force of the spring 106 should not be sufficient to return the drilling spindle 30 to its starting position on its own, two return chains 110 act on the inside end of the feed transmission link 60, which, after passing through, are arranged accordingly Deflecting rollers 112 can be wound onto one of the two winding drum sections 88 and 90 in the opposite sense. The deflection rollers 112 are spring-mounted as tension rollers in the housing 22, in that a roller tappet 114 is guided in a bore 116 of the housing 22 and is loaded by a compression spring 118.

The chains 98 and 110 are so-called flyer chains. Since the chains 110 only have to apply a retraction force in addition to the spring 106, and this will be comparatively low, it does not matter that the chains 110 act eccentrically on the feed transmission member 60. In order to visibly indicate the respective feed distance, the axis of rotation 84 carries, outside the housing 22, at its end opposite the turnstile 86, an adjustable scale drum 120 which is opposite a marking 122 on the bulge 82 of the housing 22. In addition, the above-described embodiment allows the axis of rotation 84 with the associated parts to be inserted the other way round into the housing bulge 82, and thus to make the feed drive suitable for left-handers.

In comparison to the known drilling sleeve mentioned at the beginning, the feed drive described above allows the axis of rotation of the feed drive member (turnstile 86) to be relatively close to the milling head, e.g. 10, to arrange, whereby, despite the compact construction, it occurs at a sufficient distance from the workpiece.

Since the drilling pin described so far is a precision mechanical device which, as such, naturally must not be subjected to excessive forces, on the other hand, especially if the axis of rotation of the feed drive member (turnstile 86) is relatively long because of a relatively unloading milling head If uncontrollable forces could be introduced into the drilling sleeve, an overload protection is provided. In this sense, the physical axis of rotation 84 ends outside the housing bulge 82 in a ball head 124 which surrounds a coaxial, approximately conical recess 126 which extends into the interior of the housing bulge 82, while a hub part 128 of the turnstile 86 faces one end of the ball head 124 has a matching spherical boundary surface 130. Corresponding spherical catch recesses 132 are incorporated in the spherical head 124 as well as in the spherical delimitation surface 130, which receive spheres 136 guided by a spherically curved cage 134. The balls 136 plate springs 138 provided in the hub part 128 are held under pressure via a tie rod 140, so that the balls 136 endeavor to keep the ball recesses 132 on both sides in correspondence. The tie rod 140 consists of a flexible spring steel rod which is anchored in the axis of rotation 84 and which, when the balls 136 disengage, overcoming the spring force applied by the plate springs 138, is able to bend within the conical recess 126 and then return to its original to take a straight form. In this way, the axis of rotation 84 with the subsequent parts is protected against excessive turning and bending forces. Accordingly, i.ü. also the storage of the housing 22 is made relatively light and space-saving, which in turn benefits the desired short overall length of the drilling sleeve.

The modified embodiment according to Figures 3 to 5 differs from ^'those of Figures 1 and 2 only by the design of the mounted on the housing 22 the clamping ring, here designated 70 *, and the accommodated in the Gehäuseausbuchtung 82 körperli¬ chen axis of rotation, here designated 84 ', including adjoining parts, which is why the other parts are not specifically labeled and described.

The clamping ring 70 'is interrupted by an axial slot 142 and surrounded by a wire spring 146 lying in a groove 144. The two ends 148 of the wire spring 146 appearing in the area of the slot 142 have eyelet-like bends 150 which are accommodated in a clip-like cap 152 in such a way that they are joined together by the cap 152 and the part of the wire spring 146 therebetween is thus held elastically under tension become. In this way, the housing 22 is held in the clamping ring 70 in such a way that it does so is prevented from participating in the rotation of the drilling spindle 30, but on the other hand - should the turnstile 86 in its current position be a hindrance - it can be easily pivoted relative to the milling head 10 around the spindle axis 76 into another position.

Furthermore, in contrast to the clamping ring 70 of FIGS. 1 and 2 for securing against rotation relative to the milling head 10, the clamping ring 70 'has two locking bolts 154 and 156, which are able to snap into the heads 158 of hexagon socket screws 160, as are usually ring-shaped for fixing the Bearing caps on such milling heads are used.

The latching bolts 154 and 156 are, substantially axially extending, each mounted in a substantially rectangularly profiled recess 162 within an eye 164 and 166 of the clamping ring, respectively, such that they can move longitudinally therein and can experience a radial inclination while they are in relation to tangential forces are guided relatively precisely. The ratchet pins are fixed in the recess 162 by a tangential pin 168, which extends through an elongated hole 170 of the respective locking pin, and a helical compression spring 174, which is received by a longitudinal bore 172 of each locking pin and is supported on the pin 168, presses 3 upwards. At its upper end, the locking bolt has a taper 176 suitable for engagement in the respective screw head 158.

This type of rotation lock eliminates any changes to the milling head in question. Two eyes, 164 and 166, with corresponding locking bolts 154 and 156 are provided in the example described because the mounting radius and type of screws 160 are different for milling heads from different manufacturers or even for horizontal and vertical Generally distinguish milling heads from one and the same manufacturer. If necessary, more than two eyes can also be provided with locking bolts on the clamping ring 170. On the other hand, a receptacle for a locking pin such as 154 can also be created by introducing a single small blind hole into the milling head or bearing cover in question.

The physical axis of rotation 84 'of the drill quill shown in FIGS. 3 and 4 has two ends 178 of the same design, each of which, in the usual way, each has a partially closed cross bore 180 with locking balls 182 and an intermediate helical compression spring 184. Outside the locking device formed in this way, the ends 178 of the axis of rotation 84 'are tapered, ending in cylindrical pins 186, while inside the locking device driving pins 188 are guided diagonally through the axis of rotation 84. The correspondingly designed scale drum 120 'and, on the other hand, a hub part 128' are latched onto the same plug arrangements 190 formed in this way, which are correspondingly profiled on the inside for this purpose or provided with diagonal grooves 192 on the front for receiving the relevant driving pin 188. That the scale drum 120 'and the hub part 128' are interchangeable. In addition, the scale drum 120 'has a reversible scale ring 194. As a result of this and the fact that the housing 22 can be easily rotated by, for example, 180 ° by means of the clamping ring 70 ', the drill quill in question is equally suitable for left-handers as for right-handers, and the changeover can be carried out quickly and easily.

For overload protection (which in this case is limited to rotational forces), the hub part 128 'has a first hub body 196, which is on its outside end face. has a number, for example four, of a central extension 198 of this hub body running radially outwards, semi-cylindrical locking recesses 200. The latching recesses 200, together with such latching recesses 202 of a second hub body 204, accommodate cylindrical latching bodies 206. To illustrate the mode of operation, the upper half of the second hub body 204 in FIG. 3 is drawn in its normal position with respect to the first hub body 196, whereas the lower half together with the parts 206 and 208 are drawn in the disengaged state.

The latching bodies 206 are guided in the manner of a roller bearing in a cage 208 and through one of the first, such as partially. also the plastic ring 210 surrounding the second hub body 196 or 204 is prevented from falling out. A helical compression spring 214 surrounding the extension 198 and received by a corresponding inside extension 212 of the second hub body 204, which is supported on a nut 216 attached to the end of the extension 198, presses the second hub body 204 against the first , 196, whereby the cylindrical locking bodies 206 are normally prevented from leaving the locking recesses 200 and 202. However, if excessive torque is applied by means of the turnstile 86 adjoining the second hub body 204, the first hub body 196 remains behind the second while overcoming the force of the spring 214 by the latching bodies 206. The spring tension and thus also the releasing force in question can be set with the nut 216.

Claims

- \ 2 — Claims:

1. Drill sleeve for insertion into milling spindles, with a drive spindle that can be immovably coupled to the tool holder of the milling spindle, a housing that is rotatably mounted on the drive spindle and that can be rotatably fixed to the bearing assembly of the milling spindle, and a telescopically extendable housing that is guided by the drive spindle and that is guided with the drive spindle non-rotatably coupled, equiaxed drilling spindle, a feed transmission member rotatably but axially immovable with respect to the drilling spindle and axially displaceable with respect to the housing but non-rotatably mounted, and a manually operable feed actuator, which is mounted in the housing with a transverse physical axis of rotation and is geared to the feed transmission member - Drive member with which the feed transmission member together with the drilling spindle with respect to the drive spindle is to be given an axial feed movement, characterized in that the feed transmission member (60) is designed as a sleeve surrounding the drilling spindle (30) and is suspended at two diametrically opposite points (102) on two parallel chains (98), which initially run in the direction of advance and then over both sides at the outlet end of the housing (22 ) arranged deflecting rollers (104), on which the rotary axis (84) of the feed drive element (86) and which is connected to the rotationally fixedly connected winding drum (92) can be wound up.

2. Drill quill according to claim 1, characterized in that at least one further, in the opposite direction on the feed transmission member (60) attacking chain (110) after passing through a deflection roller (112) which is also mounted in the housing (22) can be wound in the opposite direction on the winding drum (92).

3. Drilling quill according to claim 2, characterized in that the deflection roller (112) of the further chain (110) is spring-mounted as a tensioning roller in the housing (22).

4. Drill quill according to one of the preceding claims, characterized in that the chains (98, 110) are flyer chains.

5. Drill quill according to one of the preceding claims, characterized in that the two-sided chains (98, 104) receiving Wickeltrommelab¬ sections (88, 90) -differentialgetriebem. .Mit the Dreh¬ axis (84, 84 ') of the feed drive member ( 86) are connected, preferably in that they are mounted separately from one another on the axis of rotation and are coupled to one another as with a driver (94) on the axis of rotation via a differential bar (96).

6. Drill quill according to one of the preceding claims, characterized in that the feed drive member (86) with its physical axis of rotation (84; 84 ') via a flexible overload and / or bend overload protection, preferably in the form of a rolling body detent (124 -140; 196-216).

7. Drilling quill according to one of the preceding claims, characterized in that the drilling spindle (30) is suspended in a manner known per se from a return spring (106) anchored in the drive spindle (4).

8. Drilling quill according to one of the preceding claims, characterized in that the drilling spindle (30) itself, immediately after the feed transmission member (60), carries the chuck (38) or a comparable clamping device.

9. Drilling quill according to one of the preceding claims, characterized in that the housing (22) on the drive spindle (4) and / or the feed transmission member (60) on the drilling spindle (30) with a single four-point bearing (20 or 58) is stored.

10. Drill quill according to one of the preceding claims, characterized in that the housing (22) against a turn rotatably with the Lager¬ assembly (10) of the milling spindle (12) couplable clamping ring (70; 70 ') around the spindle axis (76) is adjustable.

11. Drill quill according to claim 10, characterized in that the clamping ring (70; 70 ') with at least one part (80; 160) of the bearing assembly (10) has latching means (74; 154, 156) to be snapped into place .

12. Drilling quill according to one of the preceding claims, characterized in that the feed drive member (86) and a scale drum indicating the feed path (120 ¹ ) are interchangeable on the two ends of the physical axis of rotation (84 ') of the feed drive member (86) are attachable.

13. drilling spindle sleeve according to claim 12, characterized ^"geenn ¬ characterized in that the scale drum has (120 ') has a separate cash umkehr¬ scale ring (194).