Screw drive

Abstract

A screw drive includes a spindle and a nut with a nut body. The nut body has at least one hole for a fastening member that is configured to enable the screw drive to be fastened on a higher-level subassembly or on a higher-level construction component. The at least one hole is further configured as a coolant duct of a coolant path. In one embodiment, an interior space between the nut body and the spindle is configured as a coolant duct.

Claims

1. A screw drive, comprising: a spindle nut having a nut body; and a spindle surrounded by the spindle nut, wherein the nut body has at least one through hole that is configured to receive a fastening member and form a coolant duct of a portion of a first coolant path, the fastening member configured to protrude from at least one end of two mutually opposite ends of the nut body and connect the spindle nut to a higher-level subassembly.

2. The screw drive according to claim 1, wherein the nut body has a flange, and wherein the at least one through hole is formed in the flange.

3. The screw drive according to claim 1, wherein the at least one through hole is a plurality of through holes.

4. The screw drive according to claim 3, wherein the two mutually opposite ends are each covered by a cover, and wherein at least one cover defines at least one fluid duct configured to fluidically connect at least two through holes.

5. The screw drive according to claim 4, wherein the at least one cover is a unitary body that encircles the spindle, and wherein the at least one fluid duct is configured as a groove in the at least one cover.

6. The screw drive according to claim 5, wherein the groove is recessed axially in the at least one cover.

7. The screw drive according to claim 3, wherein at least one first opening of each through hole is an inlet opening for a coolant, and wherein at least one second opening of each through hole is an outlet opening for the coolant.

8. The screw drive according to claim 7, wherein the two mutually opposite ends are each covered by a cover, and wherein, in the case of the plurality of through holes, the inlet openings are arranged alternately on the two ends when viewed in the circumferential direction of the nut body.

9. The screw drive according to claim 7, wherein, in the case of the plurality of through holes, the inlet opening of a first through hole is connected to one fluid connection, and the outlet opening of a further through hole is connected to a further fluid connection.

10. The screw drive according to claim 3, wherein the coolant path extends in a meandering way via the through holes from an inlet-side fluid connection to an outlet-side fluid connection.

11. The screw drive according to claim 3, wherein the two mutually opposite ends are each covered by a cover, wherein each cover defines respective fluid ducts configured to fluidically connect the through holes.

12. The screw drive according to claim 11, wherein each cover is a unitary body that encircles the spindle, and wherein each fluid duct is configured as a groove in the respective cover.

13. The screw drive according to claim 1, wherein at least one first opening of the through hole is an inlet opening for a coolant, and wherein at least one second opening of the through hole is an outlet opening for the coolant.

14. The screw drive according to claim 13, wherein the coolant is air.

15. The screw drive according to claim 1, further comprising an attachment configured to introduce fluid into an interior space disposed between the nut body and the spindle, the attachment arranged on the end of the nut body and the interior space configured as a coolant duct of a portion of a second coolant path.

16. The screw drive according to claim 15, further comprising a sealing element on the outer end section of the attachment when viewed in the longitudinal direction, wherein the sealing element has a smaller sealing gap than a further sealing element disposed on the end of the nut, and wherein the sealing elements seal off the interior space at the ends when viewed in the longitudinal direction.

17. The screw drive according to claim 15, wherein the attachment is configured as a sleeve that defines an annular feed space radially on the inside, the feed space being open toward the nut body and closed at least partially radially toward the inside, radially toward the outside, and axially toward the outside.

18. The screw drive according to claim 1, wherein an interior space disposed between the nut body and the spindle is configured as a coolant duct of a portion of a second coolant path, the second coolant path disposed substantially radially inwardly from the first coolant path.

19. The screw drive according to claim 18, wherein the first and second coolant paths have a common inlet opening and separate outlet openings.

20. The screw drive according to claim 1, wherein the nut body defines a fluid duct configured to carry coolant from the outside into an interior space disposed between the nut body and the spindle, the interior space configured as a coolant duct of a portion of a second coolant path.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Preferred illustrative embodiments of the disclosure are explained in greater detail below by means of schematic drawings, in which:

(2) FIG. 1 shows a screw drive in accordance with a first illustrative embodiment in a perspective illustration,

(3) FIG. 2 shows the screw drive from FIG. 1 in an exploded illustration,

(4) FIG. 3 shows schematically a coolant path of the screw drive from FIG. 1,

(5) FIGS. 4a to 4c show various illustrations of the screw drive from FIG. 1,

(6) FIG. 5 shows a screw drive in accordance with another illustrative embodiment in a perspective illustration,

(7) FIG. 6 shows the screw drive from FIG. 5 in a longitudinal section,

(8) FIG. 7 shows an attachment of the screw drive from FIG. 5 in a perspective illustration,

(9) FIG. 8 shows a screw drive in accordance with another illustrative embodiment in a longitudinal section.

DETAILED DESCRIPTION

(10) According to FIG. 1, a screw drive in the form of a planetary screw drive has a spindle 2, which is surrounded by a nut 4. This nut has a flange 6, which can be connected to a subassembly (not shown) by means of a multiplicity of fastening means in the form of fastening screws 8.

(11) According to FIG. 2, the flange 6 has a first and second end face 10, 12 when viewed in the longitudinal direction. An annular cover 14 is arranged on end face 10, and an annular cover 16 is arranged on end face 12. Six holes 18, which are configured as through holes and extend approximately parallel to and at a distance from the longitudinal axis of the screw drive 1, are made in the flange 6 on a pitch circle. Furthermore, cover 14 has through holes 20, and cover 16 has through holes 22. Here, six holes are in each case likewise provided, which are arranged to correspond to the hole pattern of the flange 6. The fastening screws 8 can be passed through the holes 18 to 22 and connected, in particular screwed, to a subassembly. After screw fastening, the covers 14, 16 and the flange 6, which is formed on a nut body 24, are fixed on the subassembly by means of the fastening screws 8. The holes 18 for the fastening screws 8 are advantageously used as coolant ducts in addition. These can be fluidically connected via fluid ducts 26 introduced into the covers 14 and 16. According to FIG. 2, the fluid ducts 26 of cover 16 are visible here. To seal off the holes 18 and the fluid ducts 26 with respect to the outside, sealing elements in the form of sealing rings 28 are provided.

(12) The coolant path, which is formed, in particular, by the holes 18 and the fluid ducts 26, is illustrated schematically in FIG. 3. According to FIG. 3, the circumferential surfaces are provided in the flange 6 and the covers 14, 16 and fluid connections 30, 32, see FIG. 2. The openings in the holes 18 serve either as inlet openings 34 or outlet openings 36. The inlet openings 34 of the holes 18 are formed alternately either on end face 10 or 12, see also FIG. 2. The coolant path then extends from fluid connection 32, via a first fluid duct 38, which is formed in cover 14, to the inlet opening 34 of the first hole 18. The outlet opening 36 of the first hole 18 is then connected to the inlet opening 34 of the adjacent hole 18 by fluid duct 26, which is formed in cover 16. The outlet opening 36 of said hole is then, in turn, connected to the inlet opening 34 of the next hole 18 by a fluid duct 26 provided in cover 14. Such a configuration is then provided as far as the last hole 18 when viewed in the circumferential direction in FIG. 3, which is then connected to fluid connection 30 by a fluid duct 40, which is formed in cover 14.

(13) A front view of the screw drive 1 from FIG. 1 is shown in FIG. 4a. According to FIG. 4a, a section along section line A-A from FIG. 4a is then shown. Here, it can be seen that a multiplicity of planets 42 is arranged between the nut body 24 of the nut 4 and the spindle 2. These are in thread engagement both with the nut body 24 and with the spindle 2. The planets 42 each have external toothing 44 on the ends, the toothing in each case being in engagement with a respective ring gear 46, 48 fixed in the nut body 24. A respective guide washer 50, 52 for guiding the planets 42 is arranged after the respective ring gear 46, 48, when looking outward in the longitudinal direction. A respective sealing element 54, 56 is provided after a respective guide washer, when looking outward in the longitudinal direction, said sealing elements being secured on the nut body 4 and surrounding the spindle 2. The sealing elements 54, 56 are of annular design and each have a sealing lip radially on the inside.

(14) The screw drive 1 is shown along section line B-B according to FIG. 4c. It can be seen that a fluid duct 58 is introducedradially for exampleinto the nut body 24, starting from the lateral surface thereof. This duct can be closed radially with respect to the outside. Opening into fluid duct 58 there is then a fluid duct 60 introducedaxially for exampleinto the flange 6, said fluid duct 60 extending from the end face 10, for example. Fluid duct 60 is preferably connected to fluid connection 30, see also FIGS. 2 and 3. An interior space 62 within the nut 4 can thereby additionally be supplied with a coolant.

(15) Another screw drive 64 is shown in a perspective view in FIG. 5. As an alternative or in addition to the coolant path formed by the holes 18, this drive has an attachment 66, which is secured on the end of the nut 4.

(16) According to FIG. 6, the attachment 66 is held on a circumferential groove 68, into which a sealing element is inserted in the case of a screw drive without the attachment 66, see sealing element 56 from FIG. 4b, for example. The approximately sleeve-shaped attachment 66 then has sealing element 56 in its end section remote from the nut 4. The attachment 66 furthermore has a first and a second fluid connection 70, 72, via which fluid, in particular air, can be introduced into the interior space 62.

(17) According to FIG. 7, the attachment 66 has at least one or more springs 74 extending around its end facing the nut 4, which can then engage behind the circumferential groove 68 shown in FIG. 6. An inner collar 76, in particular an annular inner collar, extends inward, in particular radially inward, from the sleeve-shaped attachment 66. A sleeve section 78 then extends inward in the axial direction from the inner collar 76 toward the nut 4, see FIG. 6. By means of the inner collar 76 and the sleeve section 76, a feed space 80 open toward the nut 4 is then formed. This space can then be supplied with air via the diametrically provided fluid connections 70 and 72. The air can then be introduced uniformly into the interior space 62 via the feed space 80. In this arrangement, a sealing gap of sealing element 54 is advantageously larger than in the case of sealing element 56, thus allowing the air supplied to escape to the outside again via sealing element 54.

(18) FIG. 8 shows a screw drive 82 in which, in contrast to the embodiment shown in FIG. 4c, only fluid ducts 58 and 60 are provided. Via these ducts, a fluid, e.g. air, can then be passed into the interior space 62 and then escape to the outside via the sealing elements 54, 56. When viewed in the axial direction, the flange 6 is preferably formed approximately centrally on the nut body 24.

(19) The cooling systems in the various embodiments shown in FIGS. 1 to 8 can also be combined.

(20) It is conceivable that the holes 18 in the nut body 24 for the fastening screws have a larger diameter than in the prior art, in comparison with a corresponding standard for example, in order to increase a flow cross section for fluid.

(21) A disclosure is made of a screw drive having a spindle and a nut. In this arrangement, the nut has a nut body. By way of example, the nut body has a hole for a fastening means to enable the screw drive to be fastened on a higher-level subassembly or on a higher-level construction component. The at least one hole can then be used as a coolant duct of a coolant path. As an alternative or in addition, provision can be made for an interior space between the nut body and the spindle to be used as a coolant duct.

LIST OF REFERENCE SIGNS

(22) 1; 64; 82 screw drive

(23) 2 spindle

(24) 4 nut

(25) 6 flange

(26) 8 fastening screw

(27) 10 end face

(28) 12 end face

(29) 14, 16 cover

(30) 18, 20, 22 hole

(31) 24 nut body

(32) 26, 38, 40, 58, 60 fluid duct

(33) 28 sealing element

(34) 30 fluid connection

(35) 32 fluid connection

(36) 34 inlet opening

(37) 36 outlet opening

(38) 42 planet

(39) 44 external toothing

(40) 46, 48 ring gear

(41) 50, 52 guide washer

(42) 54, 56 sealing element

(43) 62 interior space

(44) 66 attachment

(45) 68 circumferential groove

(46) 70, 72 fluid connection

(47) 74 spring

(48) 76 inner collar

(49) 78 sleeve section

(50) 80 feed space