DE102008000346A1 - Device for converting rotational movement into translatory movement, has cylindrical component on whose lateral area, helical guide curve and finger-type feeler element engaging with guide curve are located - Google Patents

Abstract

The device (1) has a cylindrical component (6) on whose lateral area, a helical guide curve (7) with a non-exclusive linear gradient and a finger-type feeler element (8) engaging with the guide curve are located. Another helical guide curve (7) is located on the lateral area of the component, whose gradient corresponds to the gradient of the former guide curve. Another finger-type feeler element (8) engages with the latter guide curve. The two feeler elements are connected with each other by another component (9).

Description

The The invention relates to a device for converting a rotary Movement in a translational movement according to the Features of the preamble of the first claim.

The German Patent Application No. 1 209 011 discloses a steering gear of a motor vehicle which converts a rotational movement of a steering wheel into a rotational movement of a steering column shaft, wherein the rotation of the steering column shaft is non-linearly dependent on the rotation of the steering wheel. For this purpose, the steering gear on a connected to the steering cylinder cylindrical first component, on the lateral surface of a helical guide curve is arranged with a non-linear pitch curve. With the guide cam is a probe element in the form of a finger roll engaged, which is mounted on a lever connected to the steering column shaft. Upon rotation of the steering wheel and the resulting rotation of the first component, the probe element is guided by the slope of the guide cam and the attachment to the lever, on a circular arc around the axis of rotation of the steering column shaft, whereby the lever initiates a rotational movement in the steering column shaft. In this case, the non-linear relationship between the rotation of the steering wheel and the rotation of the steering column shaft is determined by the gradient of the guide curve.

There in the known steering gear only a single probe element is engaged with the guide curve is the first Component always exposed to a one - sided load, creating a Bending load is induced in the first component, also takes place the entire Power transmission of the steering gear over the individual Tastelement, whereby both the entire probe element, and the first component at the point of contact with the probe element strong is charged. The probe element and the first component must For these reasons, the size should be large negative impact on the required installation space, the weight and on the economy of the production of the steering gear Has.

task The invention is a device for converting a rotary To create movement in a translational movement, taking between the translational movement and the rotational movement not exclusively linear relationship exists which makes the first component more uniform and smaller is loaded and the probe element is charged less than in pointed out prior art. It is characterized by the characteristics of first claim solved. Further embodiments This is evident from the subclaims.

to Solution of this task is located on the lateral surface the cylindrical first component next to the first helical Guide curve with a not exclusively linear Gradient course at least one more helical Guide curve whose slope course the slope course the first guide curve corresponds, with each guide curve a finger-like probe element is engaged. The feeler elements are in turn so connected to another component that they on a perpendicular to the longitudinal axis of the first component spanned Level with the guide curves engaged. hereby takes place upon actuation of the device between the first Component and the probe elements a relative movement, through which the rotational movement is transformed into a translatory movement becomes.

The Power transmission within the device thus takes place not over a single feeler element but over at least two, thereby increasing the specific load of the sensing elements reduced. In addition, the power transmission between the first component and the feeler elements not only in one place, which is heavy load of the probe element and the one-sided and strong Load of the first component has caused, but at several points simultaneously and everywhere where a probe element with a guide curve is engaged. To the load particularly evenly over the distribute first component and thus the bending loads against each other are the guide curves and the tactile elements advantageously evenly over the circumference of the first component distributed. That means that at one Use of two guide curves these at an angular distance of 180 ° to each other on the lateral surface of the first Component are arranged or when using three guide curves These at an angular distance of 120 ° to each other on the Jacket surface of the first component are arranged. The usage of three guide curves is particularly advantageous because here the other component on the three with the guide curves engaged scanning elements statically determined on the first Component is supported, causing a mutual tilting of the first and further component can be avoided.

In principle, the device can be realized in two different embodiments, wherein in the first embodiment, the first component, for example via a steering wheel or a motor, is rotatably driven about its longitudinal axis and the further component is rotatably held and along the longitudinal axis of the first component is displaceable , Here, the first component serves as an input element for the device on which the rotational movement is introduced into the device and the further component as an output element, to which the translational movement of the Device is tapped, for example by means of a Betätigungssange or a pull rope. The second possible embodiment, however, provides that the first component is held against rotation and is displaceable along its longitudinal axis and the other component is rotatably driven about the longitudinal axis of the first component. In contrast to the first embodiment, the further component serves as an input element of the device on which the rotational movement is introduced into the device and the first component as an output element, on which the translational movement is tapped by the device.

In A particularly preferred embodiment of the invention is the rotational movement of an electric motor by means of the device in a translatory movement, preferably an actuating rod transformed. Due to the simple mechanical structure of the device and the generally simple control of an electric motor for example, a complex to produce and to be regulated Linear electric motor to be replaced. To measure the of the device generated translational movement, the device can thereby both on the input side have a rotary encoder by which a computing device incorporating the pitch curve the guide curves of the initiated rotational movement can conclude the generated translatory movement, as well as the output side a displacement sensor through which directly on the generated translatory movement can be closed. there the measuring devices can be the translatory movement determine both absolute and incremental.

There the device has a small total number of components and structurally simple by changing the sizes the sensing elements and the first and further component to different transmission powers and installation conditions can be adjusted, it is suitable especially for use in electromechanical actuators in the sense of Linearstellern, especially in the vehicle sector, where often small or only complicated shaped installation spaces available stand. By a suitable choice of the pitch curve of the guide curves can be the positioning speed or the force within certain ranges of movement of the actuator to the prevailing there Conditions are adjusted. For example, such a Actuator for opening and closing a convertible top be used, being in the range of end positions, ie in the range the open or closed position of the top higher actuating forces are required for, as in the area between the positions, resulting from a corresponding adjusted course of the slopes the guide curves can be realized.

In a further particularly advantageous embodiment of the invention is the device a steering wheel of a wheeled vehicle coupled with at least one steerable vehicle wheel, wherein the rotational movement of the steering wheel in a translatory movement, preferably a tie rod is converted. The tie rod in turn acts on the vehicle wheel such that a rotation of the Steering wheel causes a corresponding rotation of the vehicle wheel. Optionally, the rotational movement to be converted by the device here in the sense of a power assisted steering for Part applied by a driver using the steering wheel be, partly by an electric motor, which for example depending on the force exerted on the steering wheel Actuating force activated. In the sense of a steer-by-wire system However, the steering wheel can also be mechanically separated from the device and instead use only an electric motor with the Device to be connected, which depends on the Steering wheel position initiates the rotational movement in the device. When using the device in a vehicle steering is the Slope course of the guide curves preferably such chosen that with a rotation of the steering wheel by one Steering angle in the area of a middle position of the steering, the Vehicle wheel is rotated less far than with a rotation of the steering wheel around the same steering angle in the range of a maximum impact the steering, making the steering a so-called progressive characteristic receives. This is in the middle position of the Steering a very sensitive steering of the vehicle possible, which is especially important at high speeds. simultaneously can, at a relatively small Steering angle of the steering wheel, a quick turn of the vehicle wheel can be achieved up to the maximum impact, which is especially fast Steering maneuvers such as when parking or to Auswei Chen before an obstacle is advantageous. in principle the pitch curve of the guide curves can be arbitrary, but not completely linear. This includes in principle, that it can be partially linear, whereby, for example, a with the device equipped steering a largely linear relationship between the steering angle of the steering wheel and may have the turning angle of the vehicle wheel and only in the range of maximum impact, as described, be progressive can.

in the The invention will be described below with reference to examples and drawings explained in more detail from which further advantageous Embodiments can be removed. Each show in a schematic representation,

1 a device in which the first Component is rotatably driven and the other components carrying the sensing elements rotatably and slidably mounted, wherein the rotational movement is generated by an electric motor and a steering wheel;

2 a device in which the first component is non-rotatable and is mounted displaceably and the other components carrying the scanning elements is rotatably drivable;

3 a section of the further component with a probe element arranged thereon, wherein the probe element is engaged with an indicated groove in the sense of a guide cam without play;

4 a section through the first component and a guide rail formed as a guide curve, wherein a sensing element is free of play with the guide rail engaged;

5 a vehicle steering system in which the device converts the rotational movement of the steering wheel and / or the electric motor into a translational movement of an actuating rod, which in turn controls two vehicle wheels by means of two tie rods.

At the in 1 illustrated device 1 becomes the rotational movement of an electric motor 2 and a steering wheel 3 in a translational movement of an actuating rod 4 converted, with the rotational movements of the electric motor 2 and the steering wheel 3 through with the device 1 coupled gearbox 5 be merged, whose output element designed as a shaft first component 6 is. On the lateral surface of the first component 6 There are two helical grooves in the sense of two guide curves 7 , which have an identical not exclusively linear gradient course. The guiding curves 7 are even over the circumference of the first component 6 distributed, that is, they have an angular distance of 180 ° to each other, causing the with the guide curves 7 engaged finger-like sensing elements 8th such on the first component 6 annularly enclosing another component 9 are arranged so that they are perpendicular to the longitudinal axis of the first component 6 spanned level 10 from two opposite sides with the guide curves 7 are engaged. The other component 9 is with the operating rod 4 connected and by means thereof against rotation about the longitudinal axis of the first component 6 secured. For this purpose, the actuating rod 4 a quadrangular cross-section and is rotatably and slidably in the housing 11 stored.

In the illustrated embodiment of the invention, the guide curves 7 evenly over the circumference of the first component 6 distributed, causing the feeler elements 8th on two opposite sides with the guide curves 7 are engaged and thereby on the first component 6 acting bending loads are balanced. In addition, because the power transmission between the first and the other component 6 . 9 via two feeler elements 8th takes place, halves on each probe element 8th and every guide curve 7 acting load.

In general, through the upstream of the transmission 5 attached to the device 1 adjacent rotational movement to the requirements of the device 1 be adapted, for example, that can be done on the device 1 applied torque can be reduced to protect them from overloading. The electric motor 2 or the steering wheel 3 However, you can also directly with the device 1 be connected, or the first component 6 can be considered the runner of the electric motor 2 be formed, whereby space and / or weight can be saved. Of course, in the device 1 guided rotational movement instead of an electric motor 2 or a steering wheel 3 be generated by any means, for example by a hand crank, a rotary knob or any rotary motor. Several of these means may, as described, by that of the device 1 upstream gear 5 be summarized or it may be a single agent with the gearbox 5 or directly with the device 1 be connected.

The device 1 in 2 converts a rotational movement into the housing 11 guided wave 12 in a translatory movement of two actuating rods 4 around which is on the left and right side out of the case 11 protrude, generating the rotational motion of the shaft 12 can be done in any way. The wave 12 drives over two bevel gears 13 the other component 9 on, which by means of a radial bearing and a thrust bearing rotatably driven in the housing 11 is stored. For converting the rotational movement into a translational movement, the first component is on it 6 annularly enclosing another component 9 two finger-like feeler elements 8th opposite to a perpendicular to the longitudinal axis of the first component 6 spanned level 10 attached, with the feeler elements 8th each with one of the on the lateral surface of the first component 6 arranged guide curves 7 are engaged. Here, the right and left end faces of the first component 6 with square cross-section actuating rods 4 connected in the housing 11 rotatably and ver sliding are stored, whereby the first component 6 is secured against self-rotation.

A rotation of the wave 12 is in the device shown 1 thus first deflected by 90 ° and on the other component 9 transferred, which together with the feeler elements 8th around the longitudinal axis of the first component 6 rotates. The tactile elements grip 8th in the guide curves 7 one, whereby the first component 6 translate to the left or right. This translational movement can be made from the housing 11 protruding actuating rods 4 be tapped.

The gradient of the guide curves 7 is chosen in the embodiment shown such that the actuating rods 4 in the region of the center position of the device shown here 1 during a rotation of the shaft 12 be moved less far, as with a rotation of the shaft 12 outside the center position, causing the device 1 gets a progressive characteristic. It is therefore particularly well suited for use in a vehicle steering system, which allows a more precise steering in the middle position, as in the area of a right or left steering wheel stop, where instead a fast steering is in the foreground.

Instead of as shown, the device can 1 even a single operating rod 4 have, which from one side of the housing 11 protrudes, or the first component 6 can take place instead of the actuating rods 4 rotatably and slidably in the housing 11 be stored, whereby a correspondingly long ausgestaltetes first component 6 the actuating rods 4 can replace.

3 shows a section of another component 9 with a mounted on the neck probe element 8th , as well as a shadowy part of the guide curve 7 with which the probe element 8th is engaged. The guide curve 7 and the probe element 8th are shaped and aligned zuein other, that a first contact surface 14 of the probe element 8th at a first contact surface 14 the guide curve 7 is present and one of the first contact surface 14 opposite second contact surface 15 of the probe element 8th on a second contact surface 15 the guide curve 7 is applied. As a result, the probe element 8th opposite the first component 6 in the direction of its longitudinal direction so free of play that at an initiation of a rotational movement in the device 1 Immediately a relative movement between the first component 6 and the other component 9 used, which causes the conversion of the rotational movement in the translational movement. Preferably, the probe element 8th in the area of contact surfaces 14 . 15 Flattening on which the on the feeler element 8th reduced effective surface pressure. Because the slope of the guide curve 7 is not constant, the positions of the contact surfaces change 14 . 15 on the feeler element 8th that is the contact surfaces 14 . 15 of the probe element 8th "Migrate" during a relative movement between the first component 6 and the other component 9 on the surface of the probe element 8th , By an advantageous embodiment of the probe element 8th With an elliptical cross-section can be achieved that on the probe element 8th and the guide curve 7 acting surface pressures are low and largely independent of the gradient of the guide curve 7 are. Here, the probe element 8th of course, so to the guide curve 7 be aligned that the contact surfaces 14 . 15 only "wander" on the flat sides of the elliptical shape.

The shown probe element 8th has in addition to an elliptical cross-section on a frustoconical shape, whereby the backlash between the first component 6 and the other component 9 by an axial displacement of the probe element 8th in the direction of the guide curve 7 is adjustable. To ensure freedom from play during wear of the probe element 8th and the guide curve 7 , the feeler element can 8th advantageously axially displaceable in the further component 9 be supported and by an elastic element, for example by a metal spring or a rubber element, against the guide curve ve 7 be pressed, reducing the contact surfaces 14 . 15 despite a wear permanently abut each other. The cone angle of the probe element must be 8th and that of the elastic element on the probe element 8th applied force be dimensioned such that the probe element 8th under the operation of the device 1 usual forces not from the guide curve 7 is pushed away, but also no jamming between the probe element 8th and the guide curve 7 can occur.

In 1 to 3 become the guiding curves 7 as in the lateral surface of the first component 6 incorporated recesses in the form of grooves. You can, however, as in 4 represented, also be a survey in the sense of a guide rail on which a finger-like probe element 8th is applied. Here, each probe element exists 8th from a rotatable with the other component 9 connected shaft 16 one with the shaft 16 fixedly connected carrier 17 and two fingers fixedly arranged on the carrier 18 , which from two opposite sides on the guide curve 7 issue. The first finger points 18 a first contact surface 14 on, which at the first contact surface 14 the guide curve 7 abuts and the second finger 18 has a second contact surface 15 on, which at the second contact surface 15 the guide curve 7 is applied. The rotatability of the shaft 16 opposite the other component 9 ensures that the feeler element 8th in a relative movement between the first component 6 and the second component 9 to a change the slope of the guide curve 7 can adapt. The finger 18 are here also frustoconical shaped, whereby the backlash by an axial displacement of the tact elements 8th or the finger 18 is adjustable. To ensure the freedom from wear and tear, the feeler element 8th or the fingers 18 therefore also by an elastic element against the guide curve 7 be pressed.

To reduce the friction between the fingers 18 and the guide curve 7 can the fingers 18 also be cylindrical and coaxial each carrying a rotatable roller, which instead of the finger 18 at the guide curve 7 is applied. To do that between the fingers 18 and to minimize friction occurring in the rollers, moreover, between the rollers and the fingers 18 Rolling be arranged, due to the small space preferably needle roller bearings. The finger 18 can instead also at the contact surfaces 14 . 15 be flattened and also have an elliptical cross-section.

This in 4 shown probe element 8th Of course, with a like in 1 to 3 shown groove-shaped guide curve 7 engage, with the fingers 18 then not, as in 4 shown side by side on the guide curve 7 abut, but one behind the other in the guide curve 7 issue.

At the in 5 shown use of the device 1 in a steering of a wheeled vehicle that acts from the device 1 projecting continuous actuating rod 4 on two tie rods 19 , which on each side of the wheeled vehicle with a steering lever 20 are connected. Every steering lever 20 is in turn part of a rotating stub axle 21 on which a vehicle wheel 22 is arranged, causing the vehicle wheels 22 in a translational movement of the actuating rod 4 rectified to be rotated in the appropriate steering direction. The rotational movement is in this case by a steering wheel 3 generated, in support of the driver during a steering movement of the device 1 a gearbox 5 with an electric motor 3 can be connected upstream, with which the rotational movement of the steering wheel is amplified. A sensor detects 23 from the driver to the steering wheel 3 applied force and controls accordingly the electric motor 2 at. Alternative to the electric motor 2 The steering can be a steering hydraulic 24 which, for example, by a double-acting piston, a force on the actuating rod 4 applying, with the steering hydraulics 24 also from the sensor 23 can be controlled.

Another use of the device 1 For example, it would be in a vehicle seat, where it is that of a hand crank or an electric motor 2 applied rotational movement in a translational forward or backward movement of the vehicle seat converts. In this case, the slope curve of the guide curves 7 be chosen such that the device 1 in a first adjustment allows a sensitive movement of the seat for adjusting a seating position and in a second adjustment allows rapid movement of the seat for setting an entry position.

1

contraption for converting a rotation into a translation

2

electric motor

3

steering wheel

4

actuating rod

5

transmission

6

first component

7

guide curve

8th

scanning element

9

additional component

10

Level, which is perpendicular to the longitudinal axis of the first component

11

casing

12

wave

13

bevel gear

14

first contact area

15

second contact area

16

shaft

17

carrier

18

finger

19

tie rod

20

steering lever

21

journal

22

vehicle

23

sensor

24

hydraulic steering

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 1209011 [0002]

Claims (10)

Contraption ( 1 ) for converting a rotational movement into a translational movement, comprising a cylindrical first component ( 6 ) on the lateral surface of a first helical guide curve ( 7 ) is located with a not exclusively linear pitch curve, and one with the guide curve ( 7 ) engaged finger-like first probe element ( 8th ), characterized in that on the lateral surface of the first component ( 6 ) at least one further helical guide curve ( 7 ), whose pitch curve the slope course of the first guide curve ( 7 ), with the further guide curve ( 7 ) another finger-like feeler element ( 8th ) is engaged, and the first probe element ( 8th ) and the further probe element ( 8th ) by another component ( 9 ) are connected to one another in such a way that the feeler elements ( 8th ) on a perpendicular to the longitudinal axis of the first component ( 6 ) level ( 10 ) with the guide curves ( 7 ) are engaged, whereby between the first component ( 6 ) and the first and the further probe element ( 8th ) upon actuation of the device ( 1 ) a relative movement takes place, by which the rotary movement is converted into a translatory movement. Contraption ( 1 ) according to claim 1, characterized in that the first component ( 6 ) is rotatably driven about its longitudinal axis and the further component ( 9 ) is held against rotation and along the longitudinal axis of the first component ( 6 ) is displaceable. Device according to claim 1, characterized in that the first component ( 6 ) is held against rotation and is displaceable along its longitudinal axis and the further component ( 9 ) about the longitudinal axis of the first component ( 6 ) is rotatably driven. Contraption ( 1 ) according to claim 2 or 3, characterized in that the first component ( 6 ) three evenly distributed on its circumference guide curves ( 7 ), which are formed as depressions in the sense of grooves, or elevations in the sense of rails, wherein the further component ( 9 ) the first component ( 6 ) comprises annular. Contraption ( 1 ) according to claim 2 or 3, characterized in that each probe element ( 8th ) a first contact surface ( 14 ), which at a first contact surface ( 14 ) of the respective guide curve ( 7 ) and that each probe element ( 8th ) a second contact surface ( 15 ), which at a second contact surface ( 15 ) of the respective guide curve ( 7 ), wherein the first and the second contact surfaces ( 14 . 15 ) are designed and aligned with each other such that the feeler elements ( 8th ) relative to the first component ( 6 ) are free of play in the direction of its longitudinal axis. Contraption ( 1 ) according to claim 2 or 3, characterized in that each probe element ( 8th ) of at least one cross-sectionally rounded finger ( 18 ), which at the respective guide curve ( 7 ) is applied, each key elements ( 8th ) in the region of the contact point with the respective guide curves ( 7 ) is flattened. Contraption ( 1 ) according to claim 2 or 3, characterized in that the device ( 1 ) with an electric motor ( 2 ), whereby one by the electric motor ( 2 ) converts rotary motion generated into a translatory movement. Contraption ( 1 ) according to claim 7, characterized in that the device ( 1 ) Is part of a linear electric actuator in a vehicle, wherein the translational movement provided by the linear actuator exclusively by converting the rotational movement of the electric motor ( 2 ) is produced. Contraption ( 1 ) according to claim 2 or 3 or 7, characterized in that the device ( 1 ) Is part of a steering wheel of a wheeled vehicle, wherein a steering wheel ( 3 ) with the device ( 1 ) is in operative connection that during a rotational movement of the steering wheel ( 3 ) a rotational movement is introduced into the device, and the device ( 1 ) with at least one vehicle wheel ( 22 ), that of the device ( 1 ) generated translational movement a rotation of the vehicle wheel ( 22 ). Contraption ( 1 ) according to claim 9, characterized in that the pitch curve of the guide curves ( 7 ) is designed such that during a rotational movement of the steering wheel ( 3 ) by a steering angle in the region of a middle position of the steering, the vehicle wheel ( 22 ) is rotated less far than in a rotational movement of the steering wheel ( 3 ) about the steering angle in the range of a maximum impact of the steering.