JP4217896B2 - Seat rail device - Google Patents

Description

  The present invention is a seat rail device that includes an upper rail and a lower rail that are slidable with respect to each other so that the seat can be slidably installed in the front-rear direction with respect to the vehicle, and that can detect the front-rear position of the upper rail relative to the lower rail. In particular, the present invention relates to a seat rail device that can detect the front-rear position between the rails.

  When installing a vehicle seat in an automobile or the like, the upper rail fixed to the seat cushion side and the vehicle floor surface side are fixed so that the seat can be slidable in the front-rear direction with respect to the vehicle floor surface. A seat rail device comprising a lower rail was used.

  Regarding this seat rail device, the distance between the “occupant” seated on the vehicle seat mounted on the seat rail device and the “airbag device” mounted on the steering wheel or dashboard of the vehicle is calculated. Therefore, the air bag deployment speed at the time of a vehicle collision can be arbitrarily controlled, and there is a high feeling that damage to the occupant should be minimized.

  In order to cope with such needs, for example, a technique described in Patent Document 1 has been adopted. As shown in FIG. 2 (FIG. 2) and FIG. 3 (FIG. 3), the seat rail device described in Patent Document 1 is a sensor unit (substantially U-shaped in section) attached to one rail. A combination of a magnet and a magnetic sensor (Hall IC)) and a flange member attached to the other rail. According to such a seat rail device, the flange member passes between the sensor portions (between the magnet and the magnetic sensor) according to the relative position between the one rail and the other rail. The part is cut off. Therefore, if the difference in the magnitude of the magnetic force is detected by the magnetic sensor, the relative position of the seat rail device can be detected.

  However, in the technique described in Patent Document 1, the magnetic sensor (magnet and magnetic sensor) attached to one rail and the flange member attached to the other rail are combined to function as a switch. To do. That is, although the sensor unit and the flange member are different from each other, the parts must be manufactured and assembled so that the flange member passes between the magnetic sensors. For this reason, there has been a problem that the performance as a switch is greatly influenced by the dimensional accuracy and assembly accuracy of the parts, and the production takes time.

  Further, in the technique described in Patent Document 1, it is possible to detect only whether or not the flange member exists between the sensor units. That is, it detects only whether the upper rail is located in front of or behind the sensor unit, and it is said that it is impossible to optimally control the airbag deployment speed. I had to.

  In view of the problems of the invention described in Patent Document 1, the applicant has proposed the technique described in Patent Document 2. In the embodiment shown in FIGS. 11 and 12, the seat rail device described in Patent Document 2 is disposed in a state in which the PC board (51) and the magnet are housed inside the lower rail (10). is doing. That is, since the magnet track installed on the upper rail (20) only needs to pass over the PC board (51) installed on the lower rail (10), it is easier to manufacture than the technique described in Patent Document 1. In addition, the position of the upper rail can be detected in the entire slidable range. Furthermore, by installing the position detection mechanism inside the seat rail device, it is possible to avoid the position detection mechanism from protruding outward, so that the vehicle mountability when mounted on the vehicle can be improved, This also contributes to improving the comfort of the passengers who ride in the vehicle.

However, the technique described in Patent Document 2 is mainly assumed to be applied to a “manual seat rail device”, and a configuration in which a magnetic sensor is arranged at a so-called “manual lock interval” or an integer multiple thereof. I was trying. According to this configuration, the structure is strong against temperature changes and voltage fluctuations and has excellent reliability. Further, although the position detection with higher accuracy than the technique of Patent Document 1 is realized, the detection position is the above-described manual lock. Since it is limited for every interval (generally, a pitch of 10 mm), there is a drawback that the positional accuracy is still rough.
US Pat. No. 6,053,529 (FIGS. 2 and 3) Japanese Patent Application No. 2003-62978 (FIGS. 11 and 12)

  Therefore, in view of the existence of the above problems, the present invention realizes high durability by adopting a non-contact structure position detecting means, and further, the position of the other rail with respect to one rail with fine positional accuracy. A seat rail device capable of detecting a slide position is provided.

  In order to solve the above-mentioned problems, the means adopted by the present invention are as follows.

First, the invention according to claim 1 includes an upper rail fixed to the seat cushion side and a lower rail fixed to the vehicle floor surface side so that the seat can be slidable in the front-rear direction with respect to the vehicle floor surface. In the seat rail device capable of detecting the front and rear positions of the upper rail with respect to the lower rail by detecting the magnetic member formed on the other rail by the sensor unit arranged on one rail among the rails,
The magnetic body member has a flat surface formed substantially parallel to the sliding direction in the seat rail device, and an inclined surface formed by inclining at an acute angle with respect to the flat surface,
The sensor unit includes a first magnetic sensor disposed at a position facing the flat surface and a second magnetic sensor disposed at a position facing the inclined surface on the one rail,
By simultaneously sliding the one rail and the sensor unit, the distance between the inclined surface and the second magnetic sensor is changed, and the voltage output from the first magnetic sensor and the second magnetic sensor The front-rear position of the upper rail with respect to the lower rail is detected by increasing or decreasing the difference from the output voltage.

  The invention according to claim 2 is the seat rail device according to claim 1 or 2, wherein the flat surface and the inclined surface of the magnetic member are formed at positions adjacent to each other. is there.

  The invention according to claim 3 includes an upper rail fixed to the seat cushion side and a lower rail fixed to the vehicle floor surface side so that the seat can be slidably installed in the front-rear direction with respect to the vehicle floor surface. In the seat rail device capable of detecting the front and rear positions of the upper rail with respect to the lower rail by detecting the position detection member provided on the other rail side by the sensor unit interlocking with one rail side among the rails, The position detection member has a magnetic body member and a magnetized portion, and the magnetic body member has two or more sections, and one section has a proximity section and a separation section. The magnetized portions are arranged in the same arrangement within one section, and are arranged in different combinations in relation to other sections, and the sensor unit The first magnetic sensor facing the magnetized portion and the second magnetic sensor facing the magnetic member, and by sliding the one rail and the sensor unit simultaneously, the first magnetic sensor The sensor detects where the magnetized portion array is located and recognizes where it is facing, and the second magnetic sensor detects the distance from the magnetic member and faces where in the certain section. It is characterized by detecting whether or not.

  According to a fourth aspect of the present invention, in the seat rail device according to the third aspect, the sensor unit is slidably provided via a guide provided in the position detection member.

  The present invention has the following effects by adopting the above-described means.

  First, in the first and second aspects of the invention, the voltage output from the first magnetic sensor arranged on the flat surface side is always constant, whereas the second magnetic sensor arranged on the inclined surface side. The voltage output from fluctuates depending on where the slide position is. Therefore, a difference occurs in the output voltage between both sensors, and the slide position can be detected based on the magnitude of this potential difference. Further, since the sensor unit and the magnetic member are not in contact with each other, the durability of the seat rail device can be ensured. Furthermore, since the number of magnetic sensors is two and the magnetic member can be formed of an inexpensive iron plate, the seat rail device itself can be provided at low cost.

  Next, in the invention according to claim 3 and claim 4, it is possible to detect the position with high accuracy by dividing the slide range into several sections. Further, since the sensor unit and the magnetic member are not in contact with each other, the durability of the seat rail device can be ensured. Furthermore, the distance between the second magnetic sensor and the magnetic member can be minimized by a guide that keeps the distance between the sensor unit and the magnetic member constant, and a large output voltage can be obtained from the second magnetic sensor. Therefore, the position detection capability can be improved.

  Hereinafter, a “seat rail device” according to the present invention will be described based on Example 1 and Example 2.

  First, Example 1 will be described. FIG. 1 is a side view of the seat rail device 100 according to the first embodiment. The seat rail device 100 according to this embodiment slides the upper rail 10 fixed to the seat cushion side and the lower rail 20 fixed to the vehicle floor surface side in the front-rear direction via the roller member 50 and the steel ball 51. It is configured freely.

  A sensor unit 30 is installed on the upper rail 10 via a support bracket 11, and a magnetic member 40 is provided on the lower rail 20, and the sensor unit 30 and the magnetic member 40 face each other. State.

  First, the magnetic member 40 is formed by adjoining a flat surface 41 formed substantially parallel to the sliding direction in the seat rail device 100 and an inclined surface 42 formed by inclining at an acute angle with respect to the flat surface 41. And formed.

  On the other hand, the sensor unit 30 includes a first magnetic sensor 31a facing the flat surface 41 of the magnetic member 40 and a second magnetic sensor 31b facing the inclined surface 42 as shown in the cross-sectional view of FIG. The magnet 33 is placed on the PC board 32, and the magnet 33 is disposed on the back side across the PC board, and these are housed in the case of the sensor unit 30.

  The magnetic sensor 31 detects a magnetic flux emitted from the magnet 33 and outputs a voltage. A magnet emits a magnetic flux from itself, but a larger amount of magnetic flux is emitted by bringing a magnetic body closer. In the present embodiment, since the magnet 33 is disposed on the back side of the PC board 32, the magnetic sensor 31 is disposed at a position sandwiched between the magnet 33 and the magnetic member 40. As the distance between the magnet 33 and the magnetic member 40 decreases, more magnetic flux is drawn from the magnet 33, and accordingly, the value of the voltage output from the magnetic sensor 31 increases.

  Here, as shown in FIG. 2, the distance between the first magnetic sensor 31a and the flat surface 41 is L1, and the distance between the second magnetic sensor 31b and the inclined surface 42 is L2. In the seat rail device 100 according to the present embodiment, when the upper rail 10 is moved from the rearmost end slide position to the frontmost end slide position, the state is changed from (a) to (b) in FIG. That is, since the value of L1 indicating the distance between the first magnetic sensor 31a and the flat surface 41 is unchanged at any slide position, the output value from the first magnetic sensor 31a is also substantially unchanged. However, the value of L2, which indicates the distance between the second magnetic sensor 31b and the inclined surface 42, gradually decreases as it moves from the rearmost end slide position to the frontmost end slide position. The magnetic flux is drawn, and the output value from the second magnetic sensor 31b also increases.

  As shown in Table 1, the seat rail device 100 according to the present embodiment is used as a reference “VA” based on the voltage value output from the magnetic sensor 31 at each slide position in advance when the seat rail device 100 is used in a vehicle. -VB map "is created and input to the vehicle-side control device.

The “VA-VB map” means that the “column” of the output values (VA) of the first magnetic sensor 31 a facing the flat surface 41 and the output value (VB) of the second magnetic sensor 31 b facing the inclined surface 42. )). Here, the VA corresponds to an output value at a “distance 0 mm” in VB, and by comparing the value of the VA with a “row” of a distance 0 mm, the “VA-VB map” "Column" to be applied is determined. Then, by matching the VB values in the “columns” to be applied, the “rows” that match the values are derived.

  That is, by comparing the VA value and the VB value with the “VA-VB map” and deriving a location where the “row” and the “column” intersect each other, the “distance from the last slide position” can be detected. Therefore, it is possible to detect where the second magnetic sensor 31 b faces the magnetic member 40, and as a result, the sliding position of the upper rail 10 relative to the lower rail 20 can be detected.

  In the above description, it is assumed that the first magnetic sensor 31a and the second magnetic sensor 31b are the same, but there are individual differences in characteristics in actual products. In addition, since the “VA-VB map” is created based on a Hall IC having ideal characteristics (hereinafter referred to as “virtual Hall IC”), in order to detect an accurate slide position, each Hall IC is detected. Individual differences need to be corrected.

  Table 2 shows the characteristics of the Hall IC used in the magnetic sensor 31 and is a graph showing the relationship between the magnetic flux (magnetic flux density) applied to the Hall IC and the output voltage. The two-dot chain line shows the ideal characteristics of the virtual Hall IC, and the solid line shows the actual characteristics.

First, in this embodiment, a magnetic flux of, for example, +50 mT and -50 mT is applied to a certain Hall IC-A, and the output voltage (V1A, V2A) at that time is measured. Based on the measured values, output characteristics (Vout1A, Vout2A) indicated by solid lines in Table 2 are obtained. To convert the Hall IC-A characteristics to the ideal characteristics indicated by the two-dot chain line, the output voltage VCMA when the magnetic flux applied to Hall IC-A is 0 and the magnetic flux applied to the virtual Hall IC is 0. Is added to the measured value VA (VA + (VCM-VCMA)), Hall IC-A sensitivity (slope of graph SBA = (V2A-V1A) / 100) and virtual Hall IC sensitivity (SB) = (V2-V1) / 100) as a constant C.

  For Hall IC-B, if the measured value VB is converted in the same way as above, the two Hall ICs can be corrected to the ideal characteristics, and the measured values should be appropriately matched in reference to the “VA-VB map”. It is possible to accurately detect the slide position.

  From the above, in the seat rail device 100 according to the present embodiment, by increasing or decreasing the difference (potential difference) between the voltage value output from the first magnetic sensor 31a and the voltage value output from the second magnetic sensor 31b. The slide position of the upper rail 10 can be detected. Specifically, the first magnetic sensor 31a and the second magnetic sensor 31b in the sensor unit 30 are connected to a control device on the vehicle side via a lead wire or the like, the potential difference is detected by the control device, and the upper rail 10 The slide position is determined.

  In this embodiment, the magnetic member 40 is formed as a separate member and is fixed to the side of the lower rail 20, but the present invention is not particularly limited to this configuration. You may form integrally, for example by pressing a part.

  Further, the magnetic body member 40 having the flat surface 41 and the inclined surface 42 and the sensor unit 30 may be disposed between the upper rail 10 and the lower rail 20 to reduce the size of the structure.

  Subsequently, Example 2 will be described. The seat rail device 100 according to the present embodiment enables further improvement in position detection accuracy as compared with the configuration of the first embodiment. First, Table 3 shows the relationship between “the distance from the rearmost slide position” and “the output voltage of the second magnetic sensor 31b” in the seat rail device 100 according to the first embodiment. The value of the voltage output from the second magnetic sensor 31b gradually increases as it moves from the rearmost slide position to the frontmost slide position, but when the slide position of the upper rail 10 exceeds 160 mm from the rearmost slide position. Has risen dramatically. This is because the magnetic flux density detected by the second magnetic sensor 31b rapidly increases with respect to the reduction amount of the distance L2 between the second magnetic sensor 31b and the magnetic member 40. That is, since the second magnetic sensor 31 b is particularly close to the magnetic member 40, more magnetic flux is drawn from the magnet 33 by the magnetic member 40.

In the present invention, the slide position is specified by the output value from the magnetic sensor. As can be seen from the “VA-VB map” shown in Table 1, the slide detected by a slight difference in output value. The position will change. In particular, in Table 3 above, when the distance from the rearmost slide position is 0 to 160 mm, the amount of change in the output voltage of the magnetic sensor is small, and the accuracy of the components and the like is required for accurate slide position detection. Here, it is conceivable to effectively use the range of the distance L2 between the second magnetic sensor 31b and the magnetic member 40 when the distance from the rearmost slide position in Table 3 is 160 mm or more. If the amount of change in the output value of the magnetic sensor with respect to the amount of change in the slide position increases, it becomes possible to detect the slide position more accurately.

  Therefore, in this embodiment, by using the magnetic sensor 31 and the magnetic body member 40 in close proximity, a portion with a large output change can be used, and the position detection accuracy can be further improved. It has been devised. Hereinafter, a specific configuration of the present embodiment will be described.

  4 to 8 are views illustrating the seat rail device 100 according to the second embodiment. The seat rail device 100 according to the present embodiment also has a configuration that is common to the above-described first embodiment. Hereinafter, only different parts will be described, and description of common parts will be omitted.

  FIG. 4 is a view showing the side of the seat rail device 100 according to the second embodiment, and a position detection member 45 is installed on the side of the lower rail 20. As shown in FIGS. 4 to 6, the position detecting member 45 is provided with a corrugated member 43 at the upper part of the main body of the position detecting member 45 and a magnetized portion 44 at the lower side of the main body. Guides 46 are arranged at both upper and lower ends, and the guides 46 are inserted into holes formed at upper and lower ends of the sensor unit 30 so as to be slidable.

  In the configuration of the position detection member 45, the “corrugated member 43” is formed as a “plurality of sections” by folding a narrow flat plate into a predetermined size as shown in FIG. 6. Is. Then, when the magnetic sensor is moved in the sliding direction so as to face the second magnetic sensor 31d of the sensor unit 30, as shown in FIG. "Will be repeated. According to this configuration, the voltage value output from the magnetic sensor increases when the magnetic sensor approaches the corrugated member 43 (magnetic member 40), while the voltage value decreases when the magnetic sensor moves away. Therefore, it is possible to detect where the second magnetic sensor 31d is facing in one section. Since the second magnetic sensor 31d and the corrugated member 40 repeat “proximity / separation” at close intervals, the output value from the magnetic sensor 31 can be changed greatly. In this embodiment, the corrugated member is formed of eight sections by folding back a flat plate.

  Next, the “magnetized portion 44” is configured by magnetizing a predetermined portion of the position detection member 45 main body or by embedding a magnet in the portion. As to what part is magnetized, for example, a configuration as shown in the schematic diagram of FIG. 8 (a) or (b) can be considered. In the figure, the dimension corresponding to one section of the corrugated member 43 is divided into four, and the portions indicated by “●” are magnetized. FIG. 6A shows a combination of all different sections based on the “binary system”, and it is possible to detect where the “section” the sensor unit 30 faces. On the other hand, FIG. 5B is a configuration in which “sections” are rearranged based on the above-mentioned (a), and “magnetized portion breaks” are formed at the joints between the sections as much as possible. By adopting the combination shown in (b), it is possible to minimize the influence of the detection error at the break of the “section”. 4 or 6 shows a state in which the magnetized portions 44 are arranged in the arrangement shown in FIG. 8B.

  The magnetized portion 44 may be continuously magnetized in one section without being divided in the section. It is added that the manufacturing cost can be reduced when such a configuration is adopted.

  On the other hand, the sensor unit 30 is movable in the sliding direction of the seat rail device 100 via the guide 46 of the position detection member 45, and the first magnetic sensor 31c and the second magnetic sensor 31d are connected to the PC. It is installed on the board 32.

  First, the first magnetic sensor 31 c is arranged on the PC board 32 in the same number as the number of the magnetized portions 44, and can face each of the magnetized portions 44. By adopting such a configuration, it is possible to detect what the combination of the magnetized portions 44 is, and it is possible to detect where the sensor unit 30 faces in the slide range. . Specifically, a plurality of the first magnetic sensors 31c are connected to the vehicle-side control device, and the vehicle-side control device recognizes which first magnetic sensor 31c is outputting a voltage, and is input in advance. By comparing with the combination of output voltages, it is possible to determine in which “section” the sensor unit 30 is facing.

  In the drawing, the first magnetic sensor 31c is arranged on a straight line with respect to the PC board 32. However, the present invention is not particularly limited to this configuration, and each first magnetic sensor 31c is biased forward, backward, left and right. Thus, the sensor unit 30 can be downsized. However, in the case of adopting such a configuration, it is necessary to bias the arrangement of the magnetized portion 44 in accordance with the first magnetic sensor 31c.

  Next, in the second magnetic sensor 31d, similarly to the magnetic sensors 31a and 31b in the first embodiment, the magnet 33 is disposed on the back surface via the PC board 32, and the second magnetic sensor 31d and the corrugated member 43 are disposed. As the distance L increases and decreases, the output voltage value of the second magnetic sensor 31d fluctuates, and it is possible to detect where it is facing in a certain section.

  By adopting such a configuration, first, it is detected which section the first magnetic sensor 31c faces in the entire slide range, and which section in the section the second magnetic sensor 31d faces. Since the detection is performed, the slide position of the upper rail 10 can be detected with high accuracy by using the two detection data.

  The seat rail according to the present invention is not particularly limited to the above-mentioned “control of the deployment speed in the airbag device”, but constitutes a system that automatically adjusts various devices around the driver's seat to the optimum position. It can also be used when

It is a figure which shows the side of the seat rail apparatus 100 which concerns on Example 1. FIG. It is a figure which shows the AA cross section of the seat rail apparatus 100 shown in FIG. It is a figure which shows the state which has shown the magnetic body member 40 (part) in the seat rail apparatus 100 shown in FIG. 2 from upper direction, and has arrange | positioned the magnetic sensor 31 there. It is a figure which shows the side of the seat rail apparatus 100 which concerns on Example 2. FIG. It is a figure which shows the AA cross section of the seat rail apparatus 100 shown in FIG. It is a figure which shows the position detection member 45 arrange | positioned at the side of the seat rail apparatus 100 shown in FIG. 4 from diagonally upward. It is a figure which shows the state which has shown the magnetic body member 40 (part) in the position detection member 45 shown in FIG. 6 from upper direction, and has arrange | positioned the 2nd magnetic sensor 31d there. It is a table | surface which shows an example of the arrangement | sequence of the magnetized part 44 in the position detection member 45 shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Upper rail 11 Support bracket 12 Operation bracket 20 Lower rail 21 Vehicle side attachment member 30 Sensor unit 31 Magnetic sensor 31a 1st magnetic sensor 31b 2nd magnetic sensor 32 PC board 33 Magnet 40 Magnetic body member 41 Flat surface 42 Inclined surface 43 Waveform member 44 Magnetized part (magnet)
45 Position detection member body 46 Guide 50 Roller member 51 Steel ball 100 Seat rail device

Claims (4)

An upper rail fixed to the seat cushion side and a lower rail fixed to the vehicle floor surface side so that the seat is slidable in the front-rear direction with respect to the vehicle floor surface, and one of the rails In the seat rail device that can detect the front and rear positions of the upper rail with respect to the lower rail by detecting the magnetic member formed on the other rail by the sensor unit arranged on the rail of
The magnetic body member has a flat surface formed substantially parallel to the sliding direction in the seat rail device, and an inclined surface formed by inclining at an acute angle with respect to the flat surface,
The sensor unit includes a first magnetic sensor disposed at a position facing the flat surface and a second magnetic sensor disposed at a position facing the inclined surface on the one rail,
By simultaneously sliding the one rail and the sensor unit, the distance between the inclined surface and the second magnetic sensor is changed, and the voltage output from the first magnetic sensor and the second magnetic sensor A seat rail device that detects a front-rear position of an upper rail with respect to a lower rail by increasing or decreasing a difference from an output voltage. The seat rail device according to claim 1,
The flat surface and the inclined surface of the magnetic member are formed at positions adjacent to each other. An upper rail fixed to the seat cushion side and a lower rail fixed to the vehicle floor surface side so that the seat is slidable in the front-rear direction with respect to the vehicle floor surface, and one of the rails In the seat rail device capable of detecting the front and rear positions of the upper rail with respect to the lower rail by detecting the position detection member provided on the other rail side by the sensor unit interlocked with the rail side of
The position detection member has a magnetic body member and a magnetized portion, and the magnetic body member has two or more sections, and one section has a proximity section and a separation section. ,
The magnetized portions are arranged in the same arrangement within one section, and are all arranged in different combinations in relation to other sections,
The sensor unit includes a first magnetic sensor facing the magnetized portion and a second magnetic sensor facing the magnetic member,
By simultaneously sliding the one rail and the sensor unit, the first magnetic sensor detects the magnetized portion arrangement to recognize where the section is facing, and the second magnetic sensor is a magnetic member. The seat rail device is characterized in that it is detected where it is facing in a certain section. The seat rail device according to claim 3,
A seat rail device characterized in that the sensor unit is slidably provided via a guide provided in the position detection member.