Abstract:
A vehicle includes a vehicle body, a bolster spring, a bogie supporting the vehicle body via the bolster spring and a vehicle height adjusting mechanism. The vehicle height adjustment mechanism includes an integrating device, a measuring device and an elastic force adjusting device. The integrating device integrates a first relative displacement amount at a first position between the vehicle body and the bogie and a second relative displacement amount at a second position between the vehicle body and the bogie. The measuring device measures an integrated value of the first relative displacement amount and the second relative displacement amount. The elastic force adjusting device adjusts elastic force of the bolster spring based on the integrated value so as to adjust a relative displacement amount between the vehicle body and the bogie.

Description:
RELATED APPLICATIONS 
     The present application is National Phase of International Application No. PCT/JP2009/063714 filed Jul. 28, 2009, and claims priority from, Japanese Application No. 2009-037911, filed Feb. 20, 2009, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a guideway type vehicle having a vehicle body and a bogie supporting the vehicle via a bolster spring, such as a guideway type vehicle with rubber tires, in which the height adjustment thereof is made easy by performing a high-sensitive measurement of the height of the vehicle body which changes in response to the change of the vehicle body weight. 
     2. Description of the Related Art 
     A new transportation system as a medium-capacity transportation using rubber tires traveling on a special guideway such as a new transit system and MRT, has become popular in recent years. This transportation system is usually fully automated. In some cases, the transportation system is equipped with guide wheels being guided on a guideway. 
     In this transit system, the vehicle such as a train uses an air spring as a bolster spring. The bogie supports the vehicle body via the air spring and thus the height of the vehicle body changes in response to the weight change of the vehicle body (change of the number of passengers). To keep the floor level of the vehicle constant, a height adjusting mechanism is adopted. 
     The height adjustment mechanism is explained in reference to  FIG. 5  and  FIG. 6 . In  FIG. 5  and  FIG. 6 , a vehicle  100  of the new transit system has a bogie  104  mounted under a vehicle body  102  via an air spring. Each of the bogies has one or two air springs  106  mounted in the same position as an axle  108  in a longitudinal direction of the vehicle body and symmetrically in a width direction of the vehicle. An example of the present invention illustrates a case with one air spring. 
     The bogie  104  comprises an axle housing  111  arranged in the width direction of the vehicle, the axle  108  housed in the axle housing  111 , rubber tires arranged on both sides of the axle  108 , an axle frame  112  fixed to the axle housing to support the axle housing  111 , and a guide frame  118  mounted on the axle frame  112  and supporting guide wheels  114  and  116  on an edge side of the vehicle  104  in the width direction. The vehicle  100  travels on a guideway T by the guide wheels  114  and  116  being guided by a guide rail not shown in the drawings. 
     As illustrated in  FIG. 6 , a suspension frame  120  protruding downward is fixed to the vehicle body  102  and four parallel links  122  and  124  are supported pivotally on the suspension frame  120  by one end thereof. A base part  121  is integral with the suspension frame  120  and fixed under the vehicle body. The axle frame  112  is fixed to the bogie side. The air spring  106  is installed between the base part  121  and the axle frame  112 . 
     The parallel links  122  and  124  are pivotally supported on the axle frame  112  by the other end thereof. The axle  108  is supported by a parallel link mechanism  126  formed by the parallel links  122  and  124  such that the axle  108  can move in a parallel manner in the vertical direction. In this manner, the height fluctuation of the air spring  106  is tolerated. A propeller shaft  109  is connected to the axle  108  so as to transmit the rotation of a drive motor to the rubber tires  110  via an input shaft, a hypoid gear, deferential gear and the axle  108 . 
     A compressed-air tank  128  as a supply source of compressed air, a compressed-air supply pipe  130  for supplying the compressed air from the tank  128  to the air spring  106 , and a leveling valve  132  installed in the supply pipe  130  are provided under the vehicle body  102 . The leveling valve  132  has a rotating lever  134  which is connected to a valving element of the leveling valve  132 . 
     The leveling valve  132  is mounted on the vehicle body side and houses a valving element such as a rotary valve therein. The rotation shaft  136  is integral with the valving element and protrudes outside of a casing of the leveling valve  132 . The rotating lever  134  is connected to the rotation shaft. One end of the rotating lever  134  is connected to an adjusting rod  138  and a pin disposed in a vertical direction and the other end thereof is connected to the axle  108 . The adjusting rod  138  is configured such that the length thereof can be adjusted by a means such as a turnbuckle. 
     Moreover, the air spring  106 , the leveling valve  132 , the adjusting rod  138  and the like are arranged symmetrically about a centerline O. 
     With the structure above, when the weight of the vehicle body increases due to passengers boarding, the air spring  106  is compressed and the vehicle body  102  lowers and the space between the vehicle body  102  and the bogie  104  becomes smaller. On the other hand, a tip of the rotating lever  134  is connected to the adjusting rod  138  and thus the rotating lever  134  does not move downward but rotate upward about the rotation shaft  136 . The rotating lever  134  tilts upward so as to open the leveling valve  132  and then the compressed air is supplied to the air spring  106  via the compressed-air tank  128 . In this manner, the vehicle body  102  is lifted. Once the rotating lever  134  becomes horizontal due to the lift of the vehicle body  102 , the leveling valve  132  closes and the vehicle body  102  stops lifting. 
     When the weight of the vehicle body decreases, the vehicle body moves upward and the rotating lever  134  is tilted downward about the rotation shaft  136  so as to open the leveling valve  132  and discharge the compressed air from the air spring  106 . In this manner, the vehicle body  102  lowers and the rotating lever  134  becomes horizontal. When the rotating lever becomes horizontal, the leveling valve  132  closes and the vehicle body  102  stops lowering. 
     This type of the height adjusting mechanism is disclosed in FIG. 6 and FIG. 7 of Patent Document 1 (JP2000-280900) or FIG. 10 of Patent Document 2 (JP2006-62512). 
     The air springs are arranged on both sides of the vehicle body in the width direction near the axle. The leveling valve is normally provided for each of the air springs in vicinity thereof. The leveling valve is aligned with the air spring in the longitudinal direction of the vehicle so as to make controlling the tilt in the width direction easier. 
     As described above, the rotating lever  134  tilts and then the leveling valve opens to open the compressed-air supply pipe  130 . To take measures against the hunting of the valving element, a dead-band of the tilt amount is provided in the lower limit area. For instance, the dead-band may be 0 mm to ±4 mm at the tip of the rotating lever. Accordingly, the tilt of the vehicle body is tolerated in the range of the dead-band. 
     In the guideway-type vehicle equipped with the rubber tires, the position of the leveling valve is restricted in a center area of the width direction inside the rubber tires so as not to obstruct the rubber tires. Therefore, the height fluctuation outside of the rubber tires is much greater in the dead-band. Specifically, even when the height fluctuation is 4 mm at the position where the leveling valve is installed, the height fluctuation outside the rubber tires in the width direction may be around 10 mm and exceed the allowable value of the level difference between the vehicle body and a platform. 
     In the case of the vehicle having the leveling valves on the front bogie and rear bogie, when the tilt of the adjusting valve at the front bogie is opposite to that at the rear bogie in the range of the dead-band, a twisting moment is generated in the vehicle. As for the vehicle of the new transit system whose distance is short between the front and the rear bogies, the vehicle body is tilted to either one of the sides instead of being twisted. This causes an imbalance between the height of the air spring and the pressure of the compressed air. As a result, the relationship of the actual weight of the vehicle body and the pressure of the compressed air inside the air spring becomes imbalanced in some bogies. 
     This can send a wrong information to a load-compensating device which calculates the weight of the vehicle body from the pressure of the compressed air in the air spring and controls an accelerating force and a break force of the vehicle, resulting in causing negative effects to speed control and stopping accuracy of the vehicle. It is possible to narrow the dead-band of the leveling valve to solve the issue. However, this causes more frequent hunting of the valve and the structure of the leveling valve becomes complex and expensive. 
     It is also possible to use a shorter rotating lever  134  so as to increase the sensitivity of the rotating lever which moves the adjusting rod  138  in the vertical direction. However, in the case of the vehicle with the rubber tires, the installation location of the leveling valves is restricted to the center area in the width direction as mentioned above and thus the sensitivity cannot be sufficiently improved with respect to the tilt of the vehicle in the width direction thereof. Therefore, this does not solve the issue. 
     RELATED ART DOCUMENT 
     
         
         [PATENT DOCUMENT 1] JP2000-280900 ( FIG. 6  and  FIG. 7 ) 
         [PATENT DOCUMENT 2] JP2006-62512 ( FIG. 10 ) 
       
    
     SUMMARY OF THE INVENTION 
     In view of the issues of the related art, an object of the present invention is to perform the height adjustment of the vehicle body with high precision by improving the sensitivity of measuring the height of the vehicle without making the dead-band smaller. 
     To achieve the above object, the present invention proposes a guideway-type vehicle comprising: a vehicle body; a bolster spring; a bogie which supports the vehicle body via the bolster spring; and a vehicle height adjusting mechanism which includes an integrating device, a measuring device and an elastic force adjusting device, the integrating device integrating a first relative displacement amount at a first position between the vehicle body and the bogie and a second relative displacement amount at a second position between the vehicle body and the bogie, the second position being farther than the first position from the center of the vehicle body in a width direction of the vehicle body, the measuring device measuring an integrated value of the first relative displacement amount and the second relative displacement amount, the elastic force adjusting device adjusting elastic force of the bolster spring based on the integrated value so as to adjust a relative displacement amount between the vehicle body and the bogie. 
     In the present invention, the integrated value of the first relative displacement amount and the second relative displacement amount is measured and then the elastic force of the bolster spring is adjusted based on the integrated value. Therefore, in comparison to the conventional case, the displacement of the vehicle body is at least doubled, and thus the sensitivity of measuring the height of the vehicle body can be improved. Consequently, the height adjustment of the vehicle body is made easier and with higher precision. 
     When the vehicle body is tilted in the width direction thereof, a second relative displacement amount at the second position with greater distance from the center of the vehicle body, is greater than a first relative displacement amount at the first position. Thus, the sensitivity of measuring the height of the vehicle body is more than twice as good as the conventional case. 
     Therefore, according to the present invention, the precision of adjusting the height of the vehicle body is improved and it never exceeds the allowable value of the level difference between the vehicle body and a platform. 
     Moreover, even when the leveling valve is used, the structure of the valve element of the leveling valve is not changed and thus it is not necessary to change the dead-band. As a result, the hunting of the valve does not take place. 
     As an example structure of the present invention, the integrating device of the vehicle height adjusting mechanism may be a push-pull cable housed in a cable housing, one end of the push-pull cable being fixed to the vehicle body at the second position and the cable housing is mounted on the bogie in a vertical direction of the first position and the second position, and, the measuring device of the vehicle height adjusting mechanism may include a rotating lever and a measuring part, the rotating lever being connected to the other end of the push-pull cable by means of a pin at the first position and connected to a rotation axis mounted on the vehicle body such that the rotating lever can turn around the rotation axis, the measuring part measuring a turning angle of the rotating lever. 
     In the first example structure, the second relative displacement amount is transmitted to the other end of the cable at the first position via the cable of the push-pull cable. Therefore, the displacement amount of the other end of the cable at the first position and the turning angle of the rotating lever being connected to the other end of the cable, correspond to the integrated value of the first relative displacement mount and the second relative displacement amount. The turning angle of the rotating lever is set based on the integrated value. 
     In this manner, the sensitivity of measuring the height of the vehicle body can be improved with a simple and inexpensive means with use of the push-pull cable. 
     As a second example structure of the present invention, it is preferable that the integrating device of the vehicle height adjusting mechanism includes a rotation fulcrum fixed to the bogie, a lever part being constituted of a first arm and a second arm that are formed integrally with each other and supported rotationally around the rotation fulcrum, and a second connection rod connecting the bogie and the second arm at the second position, and the measuring device of the vehicle height adjusting mechanism includes a rotating lever and a measuring part, the rotating lever being connected to the first arm via a first connection rod by means of a pin at the first position and being rotatable around to the rotation fulcrum, the measuring part measuring a turning angle of the rotating lever. 
     In the second example structure, the second relative displacement amount at the second position is transmitted to the first arm as a movement of the second arm. By measuring the movement of the first arm, the integrated value of the first and second relative displacement amounts can be measured. And the elastic force of the bolster spring is adjusted based on the integrated value. In this manner, according to the second example structure of the present invention, the sensitivity of measuring the height of the vehicle body can be improved with a simple and inexpensive device. 
     In the first example structure, it is preferable to adjust the length of the push-pull cable at the second position. By this, it is possible to adjust the length of the push-pull cable at the edge side in the width direction where it is easier to perform the maintenance and thus, the sensitivity of measuring the height of the vehicle body can be adjusted as well. 
     In the second example structure, it is preferable that a displacement amount of the first connection rod is adjustable by changing a ratio of a first distance between the rotation fulcrum of the first arm and a connection point of the first connection rod and the first arm to a second distance between the rotation fulcrum of the second arm and a connection point of the second connection rod and the second arm. 
     By this, the sensitivity of measuring the height of the vehicle body is properly adjusted and thus, the sensitivity of measuring the height of the vehicle body can be improved more than twice in comparison to the conventional case. 
     Further, in the second example structure, it is preferable to adjust a length of the second connection rod. This can change the height position of the first connection rod and the rotating lever. As a result, the sensitivity of measuring the height of the vehicle body is adjusted. 
     Furthermore, the second connection rod is located at the edge side in the width direction of the vehicle body where the maintenance is easy and thus, the maintenance workers don&#39;t need to go under the vehicle body. As a result, the maintenance becomes easy. 
     According to the present invention, the guideway-type vehicle comprises: a vehicle body; a bolster spring; a bogie which supports the vehicle body via the bolster spring; and a vehicle height adjusting mechanism which includes an integrating device, a measuring device and an elastic force adjusting device, the integrating device integrating a first relative displacement amount at a first position between the vehicle body and the bogie and a second relative displacement amount at a second position between the vehicle body and the bogie, the second position being farther than the first position from the center of the vehicle body in a width direction of the vehicle body, the measuring device measuring an integrated value of the first relative displacement amount and the second relative displacement amount, the elastic force adjusting device adjusting elastic force of the bolster spring based on the integrated value so as to adjust a relative displacement amount between the vehicle body and the bogie, and the elastic force of the bolster spring is adjusted based on the integrated value of the first and second relative displacement amounts. In comparison to the conventional case, the height displacement of the vehicle body is more than doubled at the measuring position and the sensitivity of measuring the height of the vehicle body is enhanced more than twice. As a result, the adjustment of the height of the vehicle body is made easy and with higher precision. 
     In particular, when the vehicle body is tilted in the width direction thereof, the second relative displacement amount at the second position that has greater distance from the center of the vehicle body than the first position, is integrated with the first relative displacement amount at the first position. In this manner, the sensitivity of measuring the height of the vehicle body can be more than doubled in comparison to the conventional case. 
     As described above, according to the present invention, the displacement amount between the vehicle body and the platform never exceeds the allowable limit, and when the leveling valve is used, the structure of the leveling valve is not changed and thus it is not necessary to change the dead-band. As a result, the hunting of the valve does not take place. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       [ FIG. 1 ] A front view of a guide-type vehicle in relation to a first preferred embodiment of the present invention. 
       [ FIG. 2 ] A side view of the guide-type vehicle of the first preferred embodiment. 
       [ FIG. 3 ] A front view of a guide-type vehicle in relation to a second preferred embodiment of the present invention. 
       [ FIG. 4 ] A side view of the guide-type vehicle of the second preferred embodiment. 
       [ FIG. 5 ] A front view of a guide-type vehicle of the related art. 
       [ FIG. 6 ] A side view of the guide-type vehicle of the related art. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. It is intended, however, that unless particularly specified, dimensions, materials, shape, its relative positions and the like shall be interpreted as illustrative only and not limitative of the scope of the present. 
     First Preferred Embodiment 
     A first preferred embodiment of the present invention is explained hereinafter in reference to  FIG. 1  and  FIG. 2 . In  FIG. 1  and  FIG. 2 , a vehicle  10  of the new transit system has a bogie  14  via air springs  16  mounted under the vehicle body  12 . Each of the bogies has one or two air springs  16  mounted in the same position as an axle housing  21  in a longitudinal direction of the vehicle body and symmetrically in a width direction of the vehicle body. An example of the present invention illustrates a case with one air spring. 
     The bogie  14  comprises an axle housing  21  arranged in the width direction of the vehicle body, an axle  18  housed in the axle housing  21 , rubber tires  20  arranged on both sides of the axle  18 , an axle frame  22  fixed to the axle housing  21  to support the axle housing  21 , and a guide frame  28  mounted on the axle frame  22  and supporting guide wheels  24  and  26  on an edge side of the vehicle body in the width direction. The vehicle  10  travels on a guideway T by the guide wheels  24  and  26  being guided by a guide rail not shown in the drawings. 
     As shown in  FIG. 2 , a suspension frame  30  protruding downward is fixed to the vehicle body  12  and four parallel links  32  and  34  are supported pivotally on the suspension frame  30  by one end thereof. A base part  31  is integral with the suspension frame  30  and fixed under the vehicle body  12 . The axle frame  22  is fixed to the bogie side  14 . The air spring  16  is installed between the base part  31  and the axle frame  22 . 
     The parallel links  32  and  34  are pivotally supported on the axle frame  22  by the other end thereof. The axle housing  21  is supported by a parallel link mechanism  36  formed by the parallel links  32  and  34  such that the axle housing can move in a parallel manner in the vertical direction. In this manner, the height fluctuation of the air spring  16  is tolerated. A propeller shaft  19  is connected to the axle  18  so as to transmit the rotation of a drive motor to the rubber tires  20  via the axle  18 . 
     A compressed-air tank  38  as a supply source of compressed air, a compressed-air supply pipe  40  for supplying the compressed air from the tank  38  to the air spring  16 , and a leveling valve  42  installed in the supply  40  are provided under the vehicle body  12 . 
     The leveling valve  42  is mounted on the vehicle body side and houses a valving element such as a rotary valve therein. The rotation shaft  46  is integral with the valving element and protrudes outside of a casing of the leveling valve  42 . The rotating lever  44  is connected to the rotation shaft  46 . The above structure is the same as that of the related art illustrated in  FIG. 5  and  FIG. 6 . 
     In the preferred embodiment, a push-pull cable  50  is used to measure a relative displacement amount between the vehicle body  12  and the bogie  14 . The push-pull cable  50  is constituted of a housing  52  and a cable  54  housed in the housing  52 . One end  54   a  of the cable  54  is connected to one end of a rotating lever  44  (an opposite end to the rotation shaft) via a connection rod  56  at a first position A 1  in a center area of the width direction of the vehicle body. The other end  54   b  of the cable  54  is connected to abase part  31  via a connection rod  58  at a second position A 2  on the edge side of the width direction. The base part  31  is integral with the suspension frame  30  and fixed to the vehicle body  12 . 
     As illustrated in  FIG. 2 , the first position A 1  and the second position A 2  are arranged in different places in the longitudinal direction of the vehicle body. The push-pull cable  50  is arranged diagonally to the width direction of the vehicle body. In this manner, the outer end  54   b  of the cable  54  is arranged slightly off the alignment with the rubber tires  20  in the longitudinal direction instead of being arranged on an inner side of the rubber tires  20 . 
     Moreover, as illustrated in  FIG. 1 , the outer end  54   b  is connected to the base part  31  in the vicinity of the outer edge of the vehicle body  12  and in the same position in the width direction as the outmost edge of the air spring  16 . 
     The length of the cable  54  of the push-pull cable  50  can be adjusted near the second position A 2  by a turnbuckle and the like. 
     With the above structure, when the air spring  16  moves in a vertical direction in response to the weight change of the vehicle body  12 , a relative displacement takes place between the vehicle body and the bogie at the first and second positions A 1  and A 2 . This changes the height of the inner end  54   a  of the cable  54  by an integrated amount of a first relative displacement amount at the first position A 1  and a second relative displacement amount at the second position A 2 . Subsequently, the rotating lever  44  rotates around the rotation shaft  46  for the integrated mount and the valving element of the leveling valve  42  rotates in an amount responding to the integrated amount so as to open the leveling valve  42 . 
     When the weight of the vehicle body  12  is reduced and the vehicle body moves upward, the compressed air is discharged from the air spring  16  by the opening/closing operation of the leveling valve  42  and in contrast, when the weight of the vehicle body  12  is increased and the vehicle body moves downward, the compressed air is supplied to the air spring  16  by the opening/closing operation of the leveling valve  42 . Once the rotating lever  44  returns to a horizontal position, the leveling valve  42  is closed. In this manner, the height of the vehicle body  12  is adjusted. 
     When the vehicle body  12  experiences a simple vertical movement, the integrated amount of the relative displacement amounts at the first and second position A 1  and A 2  between the vehicle body  12  and the bogie  14 , is double the relative displacement amount at the first position A 1 . Thus, the sensitivity of measuring the height of the vehicle body is doubly improved. 
     When the vehicle body  12  is tilted in the width direction thereof, the vertical movement is greater on the outer side of the vehicle body than the inner side thereof in the width direction. Specifically, the relative displacement value between the vehicle body  12  and the bogie  14  is proportional to the distance from the center O of the vehicle body. Thus, when a distance B 1  between the first position and the center O is half of a distance B 2  between the second position and the center O, a second relative displacement amount at the second position A 2  is twice as much as a first relative displacement amount at the first position A 1 . The integrated amount of the relative displacement amounts at both positions is twice as much as the relative displacement amount at the first position A 1 . Consequently, the sensitivity of measuring the height of the vehicle body is improved three times better. 
     In this manner, according to the preferred embodiment, not only the height adjustment of the vehicle body  12  is made easier but also the precision of the height adjustment is improved and the time for operating the height adjustment is shortened. 
     Particularly, the sensitivity of measuring the vehicle height when the vehicle body  12  is tilted in the width direction thereof is significantly improved. As a result, the precision of adjusting the height of the vehicle in such case is sufficiently improved, thereby solving the issue of the height difference between the vehicle body  12  and the platform. 
     Further, the measuring sensitivity to the tilt of the vehicle body  12  is enhanced and thus it is easier to balance the air springs  16  with respect to the tilt of the vehicle body  12 . As a result, the height adjustment error of the vehicle body  12  is reduced in response to the weight change of the vehicle body  12 . 
     Furthermore, the structure of the valve element of the leveling valve  42  is not changed and thus the hunting of the valve does not take place. Moreover, in the preferred embodiment, the length of the cable  54  of the push-pull cable  50  can be adjusted to increase the measuring sensitivity and the outer end of the cable  54  is arranged away from the rubber tires  20  instead of on the inner side of the rubber tires and thus, maintenance workers can easily perform such adjustment of the cable length without going under the vehicle body  12 . 
     Second Preferred Embodiment 
     Next, a second preferred embodiment is described in reference to  FIG. 3  and  FIG. 4 . In  FIG. 3  and  FIG. 4 , a lever part  60  is provided to measure the relative displacement amount between the vehicle body  12  and the bogie  14 . The lever part  60  comprises a bracket  62  fixed to the axle frame  22  which supports parallel links  32  and  34  rotatably by one end of the links, a first arm  66  and a second arm  68  that are formed integrally with each other and supported rotationally around a rotation axis  64  disposed approximately in the center of the bracket  62 . 
     The first and second arms  66  and  68  are formed integrally on both sides of the rotation axis  64 . Each of the arms  66  and  68  has a straight bar shape and forms an angle smaller than 180° opening to the bogie side so as to turn with respect to the rotation axis  64 . 
     A tip of the first arm  66  is connected to one end of the rotating lever  44  via a connection rod  70  on the inner side of the vehicle body in the width direction thereof (the first position A 1 ). A tip of the second arm  68  is connected to the suspension frame  30  via an adjusting rod  72  on the outer side of the vehicle body in the width direction thereof (the second position A 2 ). 
     As illustrated in  FIG. 4 , the first position A 1  and the second position A 2  are not in the same location in the longitudinal direction. Therefore, the lever part  60  is disposed diagonal with respect to the width direction of the vehicle body. 
     Specifically, the second position A 2  is arranged outside of the rubber tire  20  in the longitudinal direction instead of being arranged behind the rubber tire  20 . The first and second positions A 1  and A 2  are arranged in the same manner as those of the first preferred embodiment in the width direction of the vehicle body. 
     Furthermore, the length of the adjusting rod  72  can be adjusted by a turnbuckle or the like, for instance. The rest of the structure is the same as that of the first preferred embodiment and thus the same components have the same reference numbers as the first preferred embodiment and will not be explained further. 
     In this preferred embodiment, when the height of the vehicle body  12  changes in the vertical direction due to the weight change of the vehicle body  12 , the vertical movement of the tip of the second arm  68  is transmitted to the tip of the first arm  66 . Thus, the vertical movement of the tip of the first arm  66  equals to the integrated value of the relative displacement amounts between the vehicle body  12  and the bogie  14  at the first position A 1  and the second position A 2 . 
     Next, the rotating lever  44  is rotated around the rotation shaft  46  for the amount of the integrated value so as to open the leveling valve  42 . In this manner, the compressed air in the amount of the integrated value is supplied to or discharged from the air spring  16 . Once the compressed air is supplied to or discharged from the air spring and the vehicle body  12  returns to a prescribed height, the rotating lever  44  return to the horizontal position and the leveling valve  42  is closed. 
     As described above, according to the preferred embodiment in the manner similar to the first preferred embodiment, when the vehicle body  12  experiences a simple vertical movement, the sensitivity of measuring the height of the vehicle body is doubly improved. Further, when the vehicle body  12  is tilted in the width direction thereof, the vertical movement is greater on the outer side of the vehicle body than the inner side thereof in the width direction. Thus, in the case wherein a distance C 1  between the first position and the center O is half of a distance between the second position and the center O, the sensitivity of measuring the height of the vehicle body is improved three times better. 
     Therefore, the precision of adjusting the height of the vehicle body  12  can be improved and the issue of the relative height difference between the vehicle body  12  and the platform will be solved. Thus, the same function effect as the first preferred embodiment can be obtained. 
     Further, the sensitivity of measuring the height of the vehicle body in the tilted position can be improved more than three times by making the length D 2  of the second arm  68  longer than the length D 1  of the first arm, i.e. D 1 &lt;D 2 . 
     Furthermore, the resistance against the movement of the lever part  60  is only rotational resistance. Thus, the resistance against the movement of the lever part  60  is reduced in comparison with the first preferred embodiment and the sensitivity of measuring the height of the vehicle body can be further enhanced. 
     It is also possible to adjust the length of the adjusting rod  72  so as to change the height position of the connection rod  70  and the rotating lever  44 . As a result, the sensitivity of measuring the height of the vehicle body can be adjusted. 
     In such case, as shown in  FIG. 4 , the adjusting rod  72  is arranged outside of the rubber tires  20  in the longitudinal direction instead of the inner side of the rubber tires  20  and also in the vicinity of the outer edge of the vehicle body in the width direction. Therefore, maintenance workers can easily perform an adjustment without going under the vehicle body  12 . 
     Moreover, in the first and second preferred embodiments, the sensitivity of measuring the height of the vehicle body can be improved by simply making the distance shorter between the rotation shaft  46  and the connection rod  66  or  60  in the rotating lever  44 . 
     INDUSTRIAL APPLICABILITIES 
     According to the present invention, in a guideway-type vehicle such as a new transit system, the sensitivity of measuring the relative displacement amount between the vehicle body and the bogie due to the weight change of the vehicle body can be improved with a simple and inexpensive device, thereby making the height adjustment of the vehicle body easy, improving the precision of the height adjustment and diminishing the height error between the vehicle body and the platform.