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Title:
GEARSHIFT ASSEMBLY INCLUDING A POSITION SENSOR ASSEMBLY
Document Type and Number:
WIPO Patent Application WO/2017/036539
Kind Code:
A1
Abstract:
The present invention gearshift assembly for a vehicle comprising: a shift lever (2) which is mounted in a housing (40, 42) to be pivotable about a first axis, and about a second axis perpendicular to the first; a position sensor assembly mounted stationary in the housing and comprising a plurality of position sensors (50) disposed in a pattern including two paths of position sensors; a sensor triggering element mounted on an element carrier (20) which is moveably mounted in the housing and coupled to the shift lever (2) in such a manner to be able to move the sensor triggering element along said pattern of position sensors in response to pivotal shift movements; characterized in that the pattern of position sensors (50) is arranged in a horizontal plane next to the shift lever (2) at a vertical level of a lower end region thereof, and in that the carrier element (20) is moveably supported by a guide structure (32, 34) in the housing, the element carrier is coupled by a hinge (12, 24) to a link (8) which in turn is connected to the shift lever (2), and in that the coupling of the element carrier (20) by the link (8) to the shift lever and the guide structure (32, 34) of the element carrier (20) are arranged such that the element carrier performs a linear movement in response to pivoting the shift lever (2) about the first axis such that the sensor triggering element is moved along a first horizontal path of the position sensor pattern perpendicular to the first axis, and that the element carrier is pivoted about a vertical pivot axis of the guide structure (32, 34) at a distance to the sensor triggering element in response to pivoting the shift lever about the second axis such that the sensor triggering element is pivoted along a second horizontal path of the position sensor pattern.

Inventors:
KVARNSTRÖM ANDERS (SE)
Application Number:
PCT/EP2015/070175
Publication Date:
March 09, 2017
Filing Date:
September 03, 2015
Export Citation:
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Assignee:
KONGSBERG AUTOMOTIVE AB (SE)
International Classes:
F16H59/10
Foreign References:
EP1992845A22008-11-19
Attorney, Agent or Firm:
AHME, Johannes et al. (DE)
Download PDF:
Claims:
Claims

1. Gearshift assembly for a transmission of a vehicle com¬ prising : a shift lever (2) which is mounted in a housing (40, 42) to be pivotable about a first axis from a neutral posi¬ tion backwards and forwards, and about a second axis per¬ pendicular to the first from the neutral position in lat¬ eral direction to the left and to the right, a position sensor assembly mounted stationary in the housing and comprising a plurality of position sensors (50) disposed in a distributed pattern including two paths of position sensors, a sensor triggering element mounted on an element carrier (20) which is moveably mounted in the housing and coupled to the shift lever (2) in such a manner to be able to move the sensor triggering element along said pattern of position sensors in response to pivotal shift movements of the shift lever about the first and second axes, characterized in that the pattern of position sensors (50) is arranged in a hor¬ izontal plane next to the shift lever (2) at a vertical level of a lower end region thereof, and in that the car¬ rier element (20) is moveably supported by a guide struc¬ ture (32, 34) in the housing, the element carrier is coupled by a hinge (12, 24) to a link (8) which in turn is connected to the shift lever (2), and in that the coupling of the element carrier (20) by the link (8) to the shift lever and the guide structure (32, 34) of the element car- rier (20) are arranged such that the element carrier per¬ forms a linear movement in response to pivoting the shift lever (2) about the first axis such that the sensor trig¬ gering element is moved along a first horizontal path of the position sensor pattern perpendicular to the first axis, and that the element carrier is pivoted about a verti¬ cal pivot axis of the guide structure (32, 34) at a dis¬ tance to the sensor triggering element in response to piv¬ oting the shift lever about the second axis such that the sensor triggering element is pivoted along a second horizontal path of the position sensor pattern.

2. Gearshift assembly according to claim 1, characterized in that the guide structure comprises a pivot pin (34) sta¬ tionary in the housing, and in that the element carrier (20) comprises a fork portion (22) providing an elongated slot, and in that the pivot pin (34) is received in the elongated slot of the fork portion (22) such that the ele¬ ment carrier (20) is able to perform the linear movement by letting the pivot pin (34) slide relative to the elon¬ gated slot of the fork portion (22) and such that the ele¬ ment carrier (20) is able to perform the pivotal movement by letting the fork portion (22) of the element carrier pivot about the pivot pin (34) .

3. Gearshift assembly according to claim 2, characterized in that the pivot pin (34) pivot pin has an enlarged tip that extends laterally over the fork portion (22) of the ele¬ ment carrier to prevent movement of the element carrier (20) in axial direction of the pivot pin.

4. Gearshift assembly according to claim 2 or 3, characterized in that the gearshift assembly and its element carri¬ er (20) are arranged such that, when the gearshift assem¬ bly is mounted in a vehicle and the shift lever is in the neutral position with respect to second pivotal axis, the first pivotal axis is oriented perpendicular to the longi¬ tudinal direction of the vehicle, and that the slot of the fork portion (22) of the element carrier is extending parallel to the longitudinal direction such that the element carrier performs a linear movement in longitudinal direc¬ tion in response to pivoting the shift lever about the first axis such that the sensor triggering element moves along the first path of position sensors which extends in the longitudinal direction of the vehicle.

5. Gearshift assembly according to claim 4, characterized in that the fork portion (22) of the element carrier (20) is disposed at an end portion of the element carrier remote from the link (8) and the shift lever (2) in forward di¬ rection, wherein the opening of the elongated slot of the fork portion (22) is facing away from the link and the shift lever.

6. Gearshift assembly according to any of the preceding claims, characterized in that the hinge (12, 24) connect¬ ing the link to the element carrier is formed as a ball j oint .

7. Gearshift assembly according to any of the preceding claims, characterized the link (8) is connected to the shift lever by a swivel connection which comprises two op¬ posite openings formed at the lower end region of the shift lever (2), and the link is formed with a bifurcated end portion being provided with two opposite pins facing each other to be received the opposite openings of the shift lever.

8. Gearshift assembly according to any of the claims 1 to 6, characterized the link (8) is connected to the shift lever by a swivel connection which comprises a mounting pin (4) formed at the lower end region of the shift lever (2) with two opposite end portions, and the link is formed with a bifurcated end portion being provided with two opposite holes in the legs of the bifurcated end portion facing each other for receiving the opposite end portions of the mounting pin (4) .

9. Gearshift assembly according to any of the preceding claims, characterized the link (10), the element carrier (20) and the pivot pin (34) of the guide structure are ar¬ ranged such that a movement of the shift lever end region about the second axis is transmitted to a movement of the sensor triggering element with a transmission ratio of greater than 1.

10. Gearshift assembly according to any of the preceding claims, characterized in that the first and second paths of the position sensors (50) intersect and are extending perpendicular to each other.

Description:
Gearshift assembly including a position sensor assembly

The present invention is directed to a gearshift assembly for a transmission of a vehicle comprising a shift lever which is mounted in a housing to be pivotable about a first axis from a neutral position backwards and forwards, and about a second axis perpendicular to the first from the neutral position in lateral direction to the left and to the right; a position sensor assembly mounted stationary in the housing and compris ¬ ing a plurality of position sensors disposed in a distributed pattern including two paths of position sensors; and a sensor triggering element mounted on an element carrier which is moveably mounted in the housing and coupled to the shift lever in such a manner to be able to move the sensor triggering element along said pattern of position sensors in response to pivotal shift movements of the shift lever about the first and second axes.

Such gearshift assemblies are for example utilized in shift- by-wire gearshift assembly assemblies or in Tip-Tronic shift ¬ ers (including mechanical PRND and a manual shifting mode) in which the positioning of the shift lever is detected by a po ¬ sition sensor assembly, and a corresponding control signal is transmitted to the transmission for actuating it in the desired manner. There is a sensor triggering element (e.g. a magnet) which is moved in response to shift lever movements along a path of position sensors, wherein a particular position sensor is activated when the sensor triggering element is positioned in close proximity to the particular position sen ¬ sor .

A gearshift assembly according to the preamble of claim 1 is disclosed in US 7,614,319 B2. A shift lever is mounted in a housing to be pivotable about a first axis, and about a second axis perpendicular to the first axis. A position sensor assembly is mounted stationary in the housing and comprises a plu ¬ rality of position sensors distributed in a planar pattern on a vertical wall. A sensor triggering element is mounted on an element carrier which is connected to the shift lever such that it follows the pivotable shift movements of the shift lever about the first axis. This movement of the element car ¬ rier is accompanied by moving the sensor triggering element along a first one of the paths of position sensors. The posi ¬ tion sensor that is in close proximity to the sensor triggering element signals the presence of the sensor triggering ele ¬ ment and thus gives an indication of the positioning of the shift lever. In the gearshift assembly disclosed there is a second path of position sensors displaced vertically above the first part of sensors. By pivoting the shift lever about the second axis the remote end of the element carrier is vertical ¬ ly moved, and in this manner the sensor triggering element may be moved between the first and second paths of the pattern of sensor elements.

The element carrier is connected to the shift lever at a posi ¬ tion spaced apart from the pivotal mounting of the shift lev ¬ er. The element carrier presses the sensor triggering element against a wall on which the pattern of position sensors is mounted. During shift movements of the shift lever the sensor triggering element slides along the wall and the position sensors. The distances the sensor triggering element travels dur ¬ ing pivotal shift movements of the shift lever depends only on the vertical distance of the sensor triggering element from the pivotal bearing of the shift lever in the housing.

For such gearshift assemblies there are two conflicting design goals. On the one hand it is desired to realize a compact gearshift assembly design. This requires that the length of the shift lever extending vertically below the pivotal bearing is limited. This implies rather short travelling distances of the lower end of the shift lever to which the element carrier is coupled when the shift lever is moved between the shift po ¬ sitions, and this in turn implies rather short distances be ¬ tween the sensor triggering element positions corresponding to the shift positions. On the other hand it is desired that the position sensor assembly gives a good spatial resolution in indicating the shift lever position, or in other words gives a reliable indication of the actual shift lever position. For this aspect it would be desirable to have the position sensors for subsequent shift positions to be spaced apart by a certain minimum distance so that the position sensor assembly can in a reliable manner discriminate between different positions of the sensor triggering element and thus of the shift lever.

Another problem of the gearshift assembly of US 7,614,319 B2 is that the position sensors are attached on a wall that is laterally displaced at distance to the shift lever and that is oriented in a vertical plane. Thus, extra space is needed on one side of the shift lever to accommodate the wall carrying the pattern of position sensors.

It is an object of the present invention to provide a gear ¬ shift assembly which allows to be realized in a compact design and which allows to accurately and efficiently discriminate between the various positions of the shift lever.

This object is achieved by gearshift assembly comprising the features of claim 1. Preferred embodiments of the invention are set out in the depended claims.

According to the present invention the pattern of position sensors is arranged in a horizontal plane next to the shift lever at a vertical level of a lower end region thereof. The carrier element is moveably supported by a guide structure in the housing, the element carrier is coupled by a hinge to a link which in turn is connected to the shift lever. The cou ¬ pling of the element carrier to the shift lever and the guide structure of the element carrier are arranged such that the element carrier performs a linear movement in response to piv ¬ oting the shift lever about the first axis such that the sen ¬ sor triggering element is moved perpendicular to the first ax ¬ is along a first horizontal path of the position sensor pat ¬ tern, and that the element carrier is pivoted about a vertical pivot axis of the guide structure at a distance to the sensor triggering element in response to pivoting the shift lever about the second axis such that the sensor triggering element is pivoted along a second horizontal path of the position sen ¬ sor pattern.

The combination of a linear horizontal movement of the sensor triggering element along a first horizontal path perpendicular to the first axis and a pivotal movement of the element carri ¬ er about a vertical pivot axis spaced apart from the sensor triggering element such that the sensor triggering element is pivoted along a second horizontal path allows for a compact design since this implies that the first and second path in ¬ tersect and that the position sensor can be arranged in a cross shape along the first and second paths such that the po ¬ sition sensor are distributed in a compact cluster. This re ¬ quires less area than two separate paths at a distance to each other. Furthermore, orienting the position sensor pattern in a horizontal plane allows to place the arrangement in close proximity in front of or behind the lower end region of the shift lever which is also in favour of a compact design.

In addition, the transmission of the pivoting of the shift lever about the second axis to a pivotal movement of the ele ¬ ment carrier permits to design this transmission with a trans- mission ratio greater than 1, which means that the sensor triggering element on the element carrier travels a larger distance than the lower end portion of the shift lever to which it is coupled. Therefore, the position sensors can be placed at larger distances to each other along the second path which improves the capability to discriminate between shift lever positions sensed by the position sensors.

In a preferred embodiment the guide structure comprises a piv ¬ ot pin stationary in the housing. The element carrier comprises a fork portion or bifurcated portion providing an elongated slot. The pivot pin is received in the elongated slot of the fork portion such that the element carrier is able to perform the linear movement by letting the pivot pin slide relative to the elongated slot of the fork portion and such that the ele ¬ ment carrier is able to perform the pivotal movement by let ¬ ting the fork portion of the element carrier pivot about the pivot pin.

In one embodiment the pivot pin has an enlarged tip that ex ¬ tends laterally over the fork portion of the element carrier to prevent movement of the element carrier in axial direction of the pivot pin. In this manner the fork portion is supported by the enlarged tip of the pivot pin in one axial direction of the pin, and by the surface from which the pin projects in the opposite axial direction, while the element carrier is still able to slide along the pivot pin in a linear motion, and to pivot about the pivot pin.

In a preferred embodiment the gearshift assembly and its ele ¬ ment carrier are arranged such that, when the gearshift assem ¬ bly is mounted in a vehicle and the shift lever is in the neu ¬ tral position with respect to second pivotal axis, the first pivotal axis is oriented perpendicular to the longitudinal di ¬ rection of the vehicle. Then the slot of the fork portion of the element carrier is extending parallel to the longitudinal direction such that the element carrier performs a linear movement in longitudinal direction in response to pivoting the shift lever about the first axis such that the sensor trigger ¬ ing element moves along the first path of position sensors which extends in the longitudinal direction of the vehicle.

In a preferred embodiment the fork portion of the element car ¬ rier is disposed at an end portion of the element carrier re ¬ mote from the link and the shift lever in forward direction, wherein an opening of the elongated slot of the fork portion is facing away from the link and the shift lever.

In a preferred embodiment the hinge connecting the link to the element carrier is formed as a ball joint.

In a preferred embodiment the link is connected to the shift lever by a swivel connection which comprises two opposite openings formed at the lower end region of the shift lever, and the link is formed with a bifurcated end portion being provided with two opposite pins facing each other to be re ¬ ceived the opposite openings of the shift lever.

In a alternative embodiment the link is connected to the shift lever by a swivel connection which comprises a mounting pin formed at the lower end region of the shift lever with two op ¬ posite end portions, and a bifurcated end portion formed on the link and being provided with two opposite holes facing each other for receiving the opposite end portions of the mounting pin. The holes can also be open at their outer ends so that ends of the legs of the bifurcated end portion have a C-shape and can be pushed onto the end portions of the mount ¬ ing pin. In a preferred embodiment the link, the element carrier and the pivot of the guide structure are arranged such that a movement of the shift lever end region about the second axis is transmitted to a movement of the sensor triggering element with a transmission ratio of greater than 1. In other words the distance travelled by the sensor triggering element in re ¬ sponse to pivoting the shift lever about the second axis is larger than the distance travelled by the end region of the shift lever to which the link is coupled.

In a preferred embodiment the first and second paths of the position sensor pattern intersect and are extending perpendicular to each other.

The invention will now be described with reference to a pre ¬ ferred embodiment shown in the drawings in which:

Fig. 1 shows an exploded view of an embodiment of the gear ¬ shift assembly;

Fig. 2 shows plan views on element carrier, link and posi ¬ tion sensor assembly in the neutral position of the shift lever (a) , shifted forward (b) and rearward (c) , and pivoted laterally to the left (d) and to the right (e) .

With reference to Fig. 1 the main components of the gearshift assembly of this embodiment will be described first, before the operation of this embodiment will be described further be ¬ low with reference to Fig. 2 further below.

Fig. 1 is an exploded view of the main components of the gear ¬ shift assembly. The gearshift assembly comprises a housing to be mounted in a vehicle. The housing is assembled by joining two housing halves 40 and 42. When the housing halves 40 and 42 are put together a spherical socket is formed inside for receiving a complementary ball portion provided on the shift lever 2. In this manner shift lever 2 is supported in the housing to be pivotable about a first axis from a neutral po ¬ sition backwards and forwards and about a second axis perpen ¬ dicular to first axis from the neutral position in lateral di ¬ rection to the left and to right. "Forwards" and "backwards" is in the longitudinal direction (driving direction= when the gearshift assembly is mounted in the vehicle. To guide shift movements the shift lever 2 comprised a detent plunger at its lower end which slides along a detent track (not shown in Fig. 1) which is stationary in the housing and which is arranged to let the shift lever engage in the shift positions of the shift pattern and to provide a haptic feedback to the driver.

Within the housing, and partially surrounding the shift lever 2 in a lower end region thereof, there is mounted a printed circuit board box 30 which houses a printed circuit board on which an array of position sensors is mounted which will be discussed in more detail below.

There is a sensor triggering element disposed within an ele ¬ ment carrier 20. The element carrier 20 comprises a box por ¬ tion at one of its ends in which the sensor triggering element is disposed, for example magnet. At the opposite end the ele ¬ ment carrier 20 is provided with bifurcated end portion 22. The element carrier 20 further comprises a ball 24 formed thereon .

The element carrier 20 is mounted in the housing such that its bifurcated end portion 22 is received between opposite guide walls 32 formed on the lower surface of the printed circuit board box 30. The guide walls 32 have inwardly extending pro ¬ jections at their edges remote from the printed circuit board box 30. In this manner the bifurcated end portion 22 of the element carrier 20 is received in the space between the oppo ¬ site guide walls 32.

In the center between the two opposite guide walls 32 a pivot pin 34 is provided. The pivot pin 34 is received within the elongated slot formed between the two legs of the bifurcated end portion 22 of the element carrier 20. In this manner the element carrier is supported in a guide structure formed by the two opposite walls 32 and the pivot pin 34 in such a man ¬ ner that it can move linearly by sliding between the two opposite guide walls 32 forth and back, and by letting the bifur ¬ cated end portion 22 of the element carrier 20 pivot about the pivot pin 34. The latter pivotal movement about pivot pin 34 lets the box portion of the element carrier opposite to the bifurcated end portion 22 move laterally to the left and to the right.

For coupling the element carrier 20 to the shift lever 2 a link 8 is provided. The link 8 has a fork or bifurcated end portion 10. The two legs of the bifurcated end portion 10 each comprise a hole on the inner side wall. The two holes being aligned and opposite to each other, and are arranged to re ¬ ceive opposite ends of a mounting pin 4 formed close to the lower end of shift lever 2. In this manner the link 8 is cou ¬ pled to the shift lever 2 by a swivel connection. Furthermore, a tongue 6 is provided on the shift lever 2 which is received in the slot between the two legs of the bifurcated end portion 10 of link 8. The tongue 6 within the slot of the bifurcated end portion 10 of the link 8 allows pivoting about the mount ¬ ing pin 4 but stabilizes the link 8 in all other directions.

Alternatively, the positioning of the mounting pins and holes could be reversed, i.e. the mounting pins could be located on the inner sides of the legs of the bifurcated end portion 10 and be aligned pointing towards each other, whereas receiving holes could be provided close to the lower end of the shift lever for receiving the mounting pins to form a swivel connection.

At its end opposite to the bifurcated end portion 10 the link 8 is provided with a upwardly projecting head in which a socket 12 is formed on the upper surface thereof. This socket 12 is arranged for receiving the ball 24 formed on the lower sur ¬ face of the element carrier 20. When the ball 24 is received within socket 12 of the link 8, element carrier 20 and link 8 are coupled by a ball joint forming a hinge connection.

For further supporting the element carrier 20 tongues 44 are provided within the housing (only tongue 44 of the left hous ¬ ing half 40 is visible in Fig. 1, but there is symmetrically provided an opposite tongue in the right housing half 42) . The tongues 44 are arranged in the housing such that the bifurcat ¬ ed end portion 10 of link 8 is disposed vertically below the tongues 44. The upwardly projecting head of the link 8 is dis ¬ posed in front of the tongues 44 such that the upper end of the projecting head with the socket 12 is disposed vertically above tongues 44. The element carrier 20 is disposed with its end portion opposite to the bifurcated end portion 22 verti ¬ cally above tongues 44 such that this part of the element car ¬ rier 20 is supported by and can slide along the upper surface of tongues 44.

In the following the operation of the gearshift assembly of this embodiment will be described with reference to Figs. 2a to 2e. Figs. 2a to 2e show schematic plan views from below, i.e. the lower end of the shift lever 2, the lower surface of the printed circuit board box 30, the link 10, the opposite tongues 44 supporting the end portion of the element carrier 20 which houses the magnet, and the element carrier 20 are visible. In addition a pattern of position sensors 50 is indi- cated (only one of the five position sensors is provided with reference numeral 50) . These position sensors 50 are disposed on a printed circuit board inside of the printed circuit board box 30, and would thus not be visible in a plan view from be ¬ low. However, for a better understanding of the invention the positions of the five position sensors 50 are indicated in Figs. 2a to 2e. The position sensors are arranged in a cross pattern forming a horizontal and a vertical path, each having three adjacent position sensors. Here and in the following the two orthogonal paths of position sensors will be referred to as a "horizontal" and a "vertical" path of sensors as they ap ¬ pear in the views of Figs. 2a to 2e. However, it should be noted that this reference to "horizontal" and vertical" is made for easier reference only in connection with Fig. 2, and that indeed the two orthogonal paths of position sensors are both disposed in a horizontal plane (Figure plane of Figs. 2a to 2e) in the gearshift assembly.

In Fig. 2a shift lever 2 is in the neutral, central position. In this position the sensor triggering element triggers the central position sensor at the intersection of the two perpendicular sensor paths.

In Fig. 2b shift lever 2 has been pivoted backwards (such that its lower end has been moved forward in the view from below in Fig. 2b) . This forward movement of the lower end of the shift lever 2 has been transferred by link 10 to element carrier 20 such that element carrier 20 has been moved forward, as can be seen by the linear forward movement of the bifurcated end por ¬ tion 22 of the element carrier 20 between the opposite guide walls 32 in Fig. 2b. The opposite end of the element carrier 20 has moved forward in the same manner in Fig. 2b such that the sensor triggering element has likewise been moved forward so that now the upper position sensor in the vertical path of position sensors in fig. 2b is activated. In Fig. 2c shift lever 2 has been pivoted forwards such that its lower end pivoted backwards in the opposite direction. Consequently, link 10 pulled element carrier 20 back, and pulled the bifurcated end portion 22 partially out of the op ¬ posing guide walls 32. Due to this backward movement of ele ¬ ment carrier 20 the sensor triggering element has been moved linearly along the vertical path of sensors to the lowest po ¬ sition sensor in the vertical path in Fig. 2c.

After the shift lever has been moved back to the neutral posi ¬ tion as shown in Fig. 2a the shift lever is now pivoted laterally such that its lower end is pivoted to the left in Figure 2d. This movement to the left is transferred by link 10 through the hinge connection 12, 24 to element carrier 20. Since the pivot pin 34 is received between the legs of the bi ¬ furcated end portion 22 of the element carrier 20, a pivotal movement of element carrier 20 about pivot pin 34 is caused. This is accompanied by a pivotal or lateral movement of the sensor triggering element at the opposite end of the element carrier 20 to the left hand side in the view of Fig. 2d such that the sensor triggering element has been moved from the central position sensor in Fig. 2a to the position sensor on the left hand side in the horizontal path of position sensors in Fig. 2d.

In Fig. 2e shift lever 2 has been pivoted laterally in the op ¬ posite direction such that its lower end has been pivoted to the right hand side in the view of Fig. 2e. As described be ¬ fore the lateral movement of link 10 is transferred to the hinge connection and to element carrier 20 such that element carrier 20 pivots about pivot pin 34 in the opposite direction and makes a lateral movement to the right hand side in the view of Fig. 2e. As a consequence, the sensor triggering ele ¬ ment in the element carrier 20 made a lateral movement to the right hand side in the view of Fig. 2e such that it is now po ¬ sitioned to activate the position sensor on the right hand side in the horizontal path of position sensors.

The distance between the pivot pin 34 and the sensor triggering element, and the relative positioning of the hinge connec ¬ tion between link 10 and element carrier 20 are arranged such that there is a transmission or gear ratio larger than 1, i.e. the sensor triggering element travels over a larger distance than the lower end region of the shift lever to which link 10 is connected. This allows to place the position sensors 50 in the horizontal path at a larger distance to each other which ensures a reliable discrimination of the positioning since ac ¬ cidental activation of two adjacent position sensors is ex ¬ cluded .