Linear drive for a closure element of a motor vehicle

Abstract

A linear drive (100) for moving a closure element of a motor vehicle relative to a body of the motor vehicle. The linear drive (100) includes an outer tube (110), an inner element (120) arranged in the outer tube (110), wherein the inner element (120) is telescopically extendable along a drive axis (A) of the linear drive (100) from an outlet end of the outer tube (110), and wherein an inner connecting element (128) is fixed to the end of the inner element (120) which is extendable from the outer tube (110), a screw spring (130) is disposed between the inner element (120) and the outer tube (110), an inner support element (122) is fixed to the inner element (120) and an outer support element (111) is fixed to the outer tube (110).

Claims

1. A linear drive for moving a closure element of a motor vehicle relative to a body of the motor vehicle, the linear drive comprising a. an outer tube having an outlet end, b. an inner element arranged at least partially in the outer tube, the inner element having an end that can be pulled out of the outer tube, i. wherein the inner element is telescopically extendable along a drive axis (A) of the linear drive through the outlet end of the outer tube, and ii. wherein an inner connecting element for connecting the linear drive to the closure element or to the body is attached to the end of the inner element, c. a screw spring arranged radially relative to the drive axis (A) and disposed between the inner element and the outer tube, d. an inner support element fixed to the inner element and coaxially aligned with the drive axis (A), and e. an outer support element non-movably fixed to the outer tube and coaxially aligned with the drive axis (A), wherein the screw spring is clamped coaxially with the drive axis (A) between the inner support element and the outer support element, characterized in that f. the linear drive comprises a securing element arranged between the screw spring and the inner connecting element and extending at least in portions around the inner element for securing the screw spring against escaping from the linear drive, wherein the securing element is disposed within a recess of the outer support element, g. wherein, radially to the drive axis (A), an outer diameter of the securing element is larger than an inner diameter of the screw spring, h. wherein, radially to the drive axis (A), an inner diameter of the securing element is smaller than an outer diameter of the inner connecting element, and i. wherein the inner element is displaceable relative to the securing element along the drive axis (A).

2. The linear drive according to claim 1, a. wherein the linear drive comprises a support element, b. wherein the outer support element is supported on the outer tube via the support element, c. wherein the securing element is arranged in the outer tube between the outer support element and the support element.

3. The linear drive according to claim 2, a. wherein the outer support element comprises a centering element for centering the inner element in the outer tube, b. wherein the centering element comprises an insertion funnel for inserting the inner element along the drive axis (A) into the outer support element and/or a number of guide tongues arranged between the inner element and the support element.

4. The linear drive according to claim 2, wherein the securing element is made of a metal with a higher heat resistance than the outer support element and/or the support element.

5. The linear drive according to claim 1, wherein the outer support element, radially relative to the drive axis (A), spaces apart the securing element from the outer tube and/or from the inner element.

6. The linear drive according to claim 1, wherein the securing element is a ring washer.

7. The linear drive according to claim 1, wherein a. the linear drive comprises a further securing element arranged between the screw spring and a drive end of the outer tube opposite the outlet end and extending at least in portions around the inner element for securing the screw spring against escaping from the linear drive, b. an outer diameter of the further securing element is larger than the inner diameter of the screw spring.

8. The linear drive according to claim 7, wherein a. the further securing element is fixed coaxially with the drive axis (A) on the inner element, and b. the further securing element (155) is displaceable relative to the outer tube (110) along the drive axis (A).

9. The linear drive according to claim 8, wherein the inner support element is arranged coaxially with axially to the drive axis (A) at least in portions between the screw spring and the further securing element.

10. The linear drive according to claim 1, wherein a. the outer support element is arranged at least in portions radially relative to the drive axis (A) between the outer tube and the screw spring, and is configured for guiding at least a first portion of the screw spring along the drive axis (A), and b. the inner support element is arranged at least in portions radially relative to the drive axis (A) between the inner element and the screw spring, and is configured for guiding at least a second portion of the screw spring along the drive axis (A).

11. The linear drive according to claim 1, wherein the screw spring is clamped between the inner support element and the outer support element such that the screw spring is compressed against a spring force of the screw spring when the inner element is pulled out of the outer tube.

12. The linear drive according to claim 1, wherein a. the outer support element is arranged at least in portions radially relative to the drive axis (A) between the outer tube and the screw spring, and is configured for guiding at least a first portion of the screw spring along the drive axis (A), and b. the inner support element is arranged at least in portions radially relative to the drive axis (A) between the inner element and the screw spring, and is configured for guiding at least a second portion of the screw spring along the drive axis (A).

13. The linear drive according to claim 1, wherein the outer support element is arranged at least in portions radially relative to the drive axis (A) between the outer tube and the screw spring, and is configured for guiding at least a portion of the screw spring along the drive axis (A).

14. The linear drive according to claim 1, wherein the inner support element is arranged at least in portions radially relative to the drive axis (A) between the inner element and the screw spring, and is configured for guiding at least a portion of the screw spring along the drive axis (A).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, objectives and properties of the invention are explained with reference to the following description and the accompanying drawings, in which exemplary subject matters according to the invention are shown.

(2) FIG. 1 shows a schematic longitudinal section of a linear drive according to the invention.

(3) FIG. 2 shows an enlarged section from FIG. 1 in the region of the securing element.

(4) FIG. 3 shows a schematic perspective view of the outer support element of a linear drive according to the invention.

(5) FIG. 4 shows a schematic longitudinal section of the outer support element from FIG. 3.

DETAILED DESCRIPTION

(6) FIG. 1 shows a schematic longitudinal section along the drive axis A of a linear drive 100 according to the invention.

(7) The linear drive 100 shown comprises an outer tube 110, which, for example, is hollow cylindrical and arranged coaxially with the drive axis, for example with a support element 119 attached to an outlet end of the outer tube 110.

(8) The linear drive 100 shown comprises an inner element 120 arranged in the outer tube 110, which for example is also hollow cylindrical and arranged coaxially with the drive axis.

(9) The inner element 120 is guided along a drive axis A of the linear drive 100, so that the inner element 120 can be extended telescopically from the outlet end of the outer tube 110, for example through the support element 119.

(10) An inner connecting element 128, for example a ball socket, is attached to the end of the inner element 120 that can be pulled out of the outer tube 110 for connecting the linear drive 100 to a closure element or to a body of a motor vehicle

(11) The linear drive 100 shown comprises a screw spring 130 arranged radially relative to the drive axis A between the inner element 120 and the outer tube 110, an inner support element 122 fixed to the inner element 120 coaxially with the drive axis A, and an outer support element 111 fixed to the outer tube 110 coaxially with the drive axis A. The screw spring 130 is clamped coaxially with the drive axis A between the inner support element 122 and the outer support element 111.

(12) For example, the outer support element 111 is supported on the outer tube 110 via the support element 119. The outer support element 111 guides the inner element 120 along the drive axis A, for example.

(13) The linear drive 100 shown comprises a securing element 150 arranged between the screw spring 130 and the inner connecting element 128 and extending around the inner element 120 for securing the screw spring 130 against escaping from the linear drive 100. The securing element 150 is, for example, a ring washer arranged in particular coaxially with the drive axis A.

(14) Radial to the drive axis A, an outer diameter of the securing element 150 is larger than an inner diameter of the screw spring 130, and an inner diameter of the securing element 150 is smaller than an outer diameter of the inner connecting element 128. The latter is illustrated in FIG. 1 by the projection P of the inner diameter of the securing element 150 along the drive axis A onto the inner connecting element 128.

(15) The inner element 120 is displaceable relative to the securing element 150 along the drive axis A, in particular through the securing element 150.

(16) The securing element 150 shown is arranged in the outer tube 110 coaxially with the drive axis A between the outer support element 111 and the support element 119, for example in a recess in a side surface of the outer support element 111 facing the support element 119.

(17) The outer support element 111 shown, radially relative to the drive axis A, spaces apart the securing element 150 from the outer tube 110 and from the inner element 120.

(18) The linear drive 100 shown comprises a further securing element 155 arranged between the screw spring 130 and a drive end of the outer tube 110 opposite the outlet end and extending around the inner element 120 for securing the screw spring 130 against escaping from the linear drive 100. The further securing element 155 is, for example, a ring washer arranged coaxially with the drive axis A.

(19) Radial to the drive axis A, an outer diameter of the further securing element 155 is larger than an inner diameter of the screw spring 130.

(20) The further securing element 155 is fixed coaxially with the drive axis A on the inner element 120, for example by a snap ring 156 arranged partially in a bead in the inner element 120 extending around the drive axis A.

(21) The further securing element 155 is arranged, for example, in the outer tube 110 and is displaceable relative to the outer tube 110 along the drive axis A.

(22) The inner support element 122 shown is arranged in portions axially with the drive axis A between the screw spring 130 and the further securing element 155.

(23) The outer support element 111 shown is arranged in portions radially relative to the drive axis A between the outer tube 110 and the screw spring 130, and is configured for the external guidance of a portion of the screw spring 130 along the drive axis A.

(24) The inner support element 122 shown is arranged in portions radially relative to the drive axis A between the inner element 120 and the screw spring 130, and is configured for the internal guidance of a portion of the screw spring 130 along the drive axis A.

(25) The shown screw spring 130 is clamped between the inner support element 122 and the outer support element 111 such that the screw spring 130 is compressed against a spring force of the screw spring 130 when the inner element 120 is pulled out of the outer tube 110.

(26) The linear drive 100 shown comprises a drive unit 140 for the motorized drive of a pull-out movement and a push-in movement of the inner element 120 from the outer tube 110 and into the outer tube 110.

(27) The drive unit 140 shown is attached to the outer tube 110 at the drive end of the outer tube 110 opposite the outlet end. The drive unit 140 comprises, for example, an electric motor 141 and a spindle gear 142 for driving the pull-out movement and the push-in movement of the inner element 120.

(28) For example, an outer connecting element 118 for connecting the linear drive 10 to the closure element or to the body is attached to an end of the drive unit 140 facing away from the outer tube 110.

(29) FIG. 2 shows an enlarged section from FIG. 1 in the region of the securing element 150.

(30) FIG. 3 shows a schematic perspective view of the outer support element 111 of a linear drive 100 according to the invention.

(31) The outer support element 111 shown comprises a centering element 117 for centering the inner element 120 in the outer tube 110. The centering element 117 shown comprises an insertion funnel 115 for inserting the inner element 120 along the drive axis A into the outer support element 111 and, for example, four guide tongues 114 to be arranged between the inner element 120 and the support element 119.

(32) The outer support element 111 shown comprises a recess 116 in a side surface of the outer support element 111 facing the support element 119 for receiving the securing element 150, wherein the recess 116 extends around the drive axis A in a ring-shaped manner, for example.

(33) The outer support element 111 shown comprises, for example, four latching tabs 113 for mounting the securing element 150 in the recess 116. The latching tabs 113 are preferably arranged on the guide tongues 114 of the outer support element 111. For example, the latching tabs 113 project radially outwards from the drive axis A over the guide tongues 114 and together form an annular projection coaxial with the drive axis A.

(34) The outer support element 111 shown comprises a spring recess 112 on a side facing away from the support element 119 for receiving a portion of the screw spring 130, wherein the spring recess 112 extends around the drive axis A in a ring-shaped manner, for example.

(35) FIG. 4 shows a schematic longitudinal section along the drive axis A of the outer support element 111 of FIG. 3.