JP2016030464A - Axle lift device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a rise amount of an axle, by restraining required force small for lifting the axle supported by a leaf spring.SOLUTION: A leaf receiving part movable mechanism 21 can be set in a lift prohibition state and a lift permission state, and is supported on the vehicle body side. An axle lifting mechanism 31 can lift an axle 6R of a rear-rear wheel 5R, and is supported on the vehicle body side. The leaf receiving part movable mechanism 21 holds a rear leaf rear end receiving part 16R in a lift prohibition position of a suspension state of regulating the upward movement of a rear end part by abutting from above on the rear end part of a lear leaf spring 8R in the lift prohibition state, and moves the rear leaf rear end receiving part 16R to a lift permission position for allowing lifting from the suspension state of the rear end part of the rear leaf spring 8R in the lift permission state.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an axle lift device that is mounted on a vehicle and lifts wheels from the ground.

  Patent Document 1 describes a large vehicle with a tire lifting mechanism. This large vehicle includes a so-called trunnion-type leaf suspension mechanism, and front and rear axles are respectively connected to a front end and a rear end of a leaf spring. One end of the wire is wound and fixed to the rear axle, and the other end of the wire is wound around a small winch. When the operation switch is turned on, the small winch winds up the wire, lifts the axle, and the tire lifts off the road surface.

Japanese Utility Model Publication No. 3-69584

  In the conventional tire lifting mechanism, the axle must be lifted while maintaining the state where the axle is biased downward by the leaf spring. For this reason, the urging force of the leaf spring becomes a resistance force against the rise of the axle, and an excessive force is required to raise the axle. Further, since the movable range of the axle is limited to the elastic deformation region of the leaf spring, there is a possibility that the tire cannot be sufficiently separated from the ground.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an axle lift device capable of suppressing a force required to raise an axle supported by a leaf spring and increasing an amount of raising the axle.

  In order to achieve the above object, a first aspect of the present invention is an axle lift device, which includes first abutting portion moving means and axle lifting / lowering means.

  The axle lift device is installed in a vehicle including first and second wheels and a suspension device arranged in the front-rear direction to lift the first wheel from a state where the first and second wheels are in contact with the ground. The suspension device includes a leaf spring, an intermediate portion in the front-rear direction of the leaf spring is connected to the axle of the first wheel, and a first contact portion on the vehicle body side is placed on one end portion in the front-rear direction of the leaf spring. In the suspended state in which the second abutment portion on the vehicle body side is placed on the other end portion in the front-rear direction of the spring, the load on the vehicle body side is elastically supported via the leaf spring by the axle of the first wheel that is grounded.

  The first contact portion moving means can be set to a lift prohibited state and a lift permitted state, and is supported on the vehicle body side. The axle raising / lowering means can raise and lower the axle of the first wheel and is supported on the vehicle body side.

  In the lift prohibited state, the first contact portion moving means holds the first contact portion in the lift prohibited position in a suspended state that contacts the one end portion of the leaf spring from above and restricts the upward movement of the one end portion. In the lift permission state, the first contact portion is moved to a lift permission position that allows the one end portion of the leaf spring to rise from the suspended state.

  In the above configuration, when the first wheel is grounded, the driver or the like sets the first contact portion moving means to the lift prohibited state. When the first abutting portion moving means is set to the lift prohibited state, the first abutting portion is held at the lift prohibited position, the suspension device is suspended, and the load on the vehicle body side is caused by the axle of the grounded first wheel. Is elastically supported via a leaf spring.

  When lifting the first wheel from the grounded state of the first and second wheels and separating them from the ground, the driver, etc., after changing the first contact part moving means from the lift prohibited state to the lift permitted state, The axle of the first wheel is raised by the axle lifting means. By changing the first contact portion moving means from the lift prohibition state to the lift permission state, the first contact portion moves from the lift prohibition position to the lift permission position. Since the movement of the first contact portion to the lift prohibition position allows the end of the leaf spring to be lifted from the suspended state, the leaf spring generally tilts as the axle is raised. Therefore, compared with the case where the axle is raised against the urging force of the leaf spring, the force for raising the axle can be kept small, and the increase in size and weight of the device can be suppressed. Further, since the movable range of the axle is not limited to the elastic deformation region of the leaf spring, the wheel can be sufficiently separated from the ground.

  According to a second aspect of the present invention, there is provided an axle lift device according to the first aspect, comprising tilt restriction means that can be set in a tilt permission state and a tilt restriction state.

  The leaf suspension device includes a second leaf spring and an equalizer mechanism. A middle portion in the front-rear direction of the second leaf spring is connected to the axle of the second wheel, and a third abutment on the vehicle body side is connected to one end portion in the front-rear direction of the second leaf spring extending from the middle portion to the first wheel side. In the suspended state where the contact portion is placed and the vehicle body side fourth contact portion is placed on the other end portion of the second leaf spring in the front-rear direction, the load on the vehicle body side is caused by the axle of the grounded second wheel. It is elastically supported via the second leaf spring. The equalizer mechanism includes an inclined member provided with a second contact portion and a third contact portion. The inclined member is supported on the vehicle body side so as to be tiltable about a rotating shaft extending in the vehicle width direction between the other end of the leaf spring and one end of the second leaf spring. The second contact portion is provided on the first wheel side with respect to the rotation shaft, and the third contact portion is provided on the second wheel side with respect to the rotation shaft.

  The tilt restricting means allows tilting of the tilting member in the tilting permitted state, and restricts tilting of the tilting member in the tilting restricting state.

  In the above configuration, when the first wheel and the second wheel are grounded, the driver or the like sets the tilt restricting means to the tilt permitting state and, similarly to the first aspect, the first abutting portion moving means. Is set to the lift prohibited state. When the tilt restricting means is set to the tilt permitting state, tilting of the tilting member is permitted and the equalizer mechanism functions, and the vehicle body side load is suitably distributed to the axles of the first and second wheels.

  When the first wheel is lifted away from the ground while the first and second wheels are in contact with the ground, the driver or the like changes the tilt restricting means from the tilt permitting state to the tilt restricting state, and then the first mode. Similarly, the first contact portion moving means is changed to the lift permission state, and the axle of the first wheel is raised by the axle lifting means. When the movement restricting means is changed to the tilt restricting state, the tilting of the tilting member is restricted. Therefore, when the axle of the first wheel is raised by the axle lifting / lowering means, the rise of the other end of the leaf spring is third. It is reliably suppressed by the contact portion. Therefore, the first wheel can be raised while reliably tilting the leaf spring with a stable behavior.

  According to the present invention, the force required to raise the axle supported by the leaf springs can be kept small, and the amount by which the axle is raised can be increased.

It is a side view which shows the axle lift apparatus of one Embodiment of this invention. It is a principal part enlarged view of FIG. It is principal part sectional drawing which looked at FIG. 1 from the III-III direction. It is principal part sectional drawing which looked at FIG. 1 from the IV-IV direction. It is principal part sectional drawing which looked at FIG. 1 from the VV direction. It is principal part sectional drawing which looked at FIG. 1 from the VI-VI direction. It is a top view of FIG. 1 which shows a leaf receiving part movable mechanism and an equalizer riser fixing mechanism. It is a top view of FIG. 1 which shows an axle raising / lowering mechanism and a leaf receiving part movable mechanism. It is a schematic diagram of a pneumatic circuit. It is a side view which shows the axle lift apparatus after an equalizer riser fixing mechanism transfers to a tilt control state. It is a side view which shows the axle lift apparatus after the leaf receiving part movable mechanism transfers to a lift permission state. It is a side view which shows the axle lift apparatus of the shaft lift state in which the rear-rear shaft was lifted. It is a principal part top view which shows the leaf receiving part movable mechanism and equalizer riser fixing mechanism of a shaft lift state. It is a principal part top view which shows the axle raising / lowering mechanism and leaf receiving part movable mechanism of a shaft lift state.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each figure, FR indicates the front of the vehicle, Rr indicates the rear of the vehicle, UP indicates the upper direction of the vehicle, L indicates the left direction, and R indicates the right direction. Moreover, the left-right direction of the following description means the left-right direction in the state which faced the vehicle front unless there is particular description.

  In the present embodiment, an axle lift device 20 mounted on a semi-trailer (vehicle) 1 that is pulled by a tractor (not shown) will be described. The vehicle equipped with the axle lift device 20 is not limited to the semi-trailer 1, and may be a truck or a trailer.

  As shown in FIGS. 1 to 8, the vehicle body of the semi-trailer 1 is constituted by a chassis frame 2. The chassis frame 2 includes a pair of left and right main beams 3 that extend substantially in parallel along the vehicle longitudinal direction, and a plurality of cross frames (not shown) that are arranged at predetermined intervals in the vehicle longitudinal direction and extend in the vehicle width direction. Have Both ends of each cross frame are coupled to the side surfaces of the main beam 3, and the chassis frame 2 is formed in a ladder shape by the main beam 3 and the cross frame.

  The front part of the chassis frame 2 is connected to a coupler (not shown) of the tractor via a king pin (not shown), and the rear part of the chassis frame 2 has a plurality of sets (three sets in this embodiment) arranged in the front-rear direction. (Tire) Supported from below by 5F, 5M, 5R. The front left and right wheels (rear front wheels) 5F are rotatably supported by a front axle (rear front axle) 6F, and the central left and right wheels (rear middle wheels (second wheels)) 5M are center axles. The rear left and right wheels (rear rear wheel (first wheel)) 5R are rotatably supported by the rear axle (rear rear shaft) 6R. The axles 5F, 5M, 5R extend along the vehicle width direction, and a suspension device 7 is provided between the left and right main beams 3 and the axles 6F, 6M, 6R.

  The suspension device 7 is a suspension device for a tandem axle by a so-called Equalizer system, and is supported by a front leaf spring 8F supported by the rear front shaft 6F, a middle leaf spring 8M supported by the rear middle shaft 6M, and a rear rear shaft 6R. The rear leaf spring 8R, the front side equalizer spring 9F provided between the front leaf spring 8F and the middle leaf spring 8M, and the rear side equalizer riser mechanism provided between the middle leaf spring 8M and the rear leaf spring 8R. 9R.

  An intermediate portion in the front-rear direction of the front leaf spring 8F is placed on the rear front shaft 6F from above, and is fastened and fixed to the rear front shaft 6F by the front shaft coupling member 10F. An intermediate portion in the front-rear direction of the middle leaf spring 8M is placed on the rear middle shaft 6M from above, and is fastened and fixed to the rear middle shaft 6M by the middle shaft coupling member 10M. An intermediate portion in the front-rear direction of the rear leaf spring 8R is placed on the rear rear shaft 6R from above, and is fastened and fixed to the rear rear shaft 6R by the rear shaft coupling member 10R.

  First to fourth hangers 11 </ b> A to 11 </ b> D are fixed to the lower surfaces of the left and right main beams 3 so as to be separated in the front-rear direction. The first hanger 11A is disposed near the front end of the front leaf spring 8F, the second hanger 11B is disposed between the front leaf spring 8F and the middle leaf spring 8M, and the third hanger 11C is the middle leaf spring. The fourth leaf spring 11D is disposed in the vicinity of the rear end portion of the rear leaf spring 8R.

  The front and rear equalizer mechanisms 9F and 9R include equalizers 12F and 12R, respectively. The front equalizer 12F includes an intermediate portion that is tiltably supported by the second hanger 11B around a rotation shaft 13F that extends in the vehicle width direction, and a front leaf rear end receiving portion 14R that is disposed in front of the rotation shaft 13F. And a middle leaf front end receiving portion (fourth contact portion) 15F disposed behind the rotating shaft 13F. The rear equalizer (tilting member) 12R has an intermediate portion that is tiltably supported by the third hanger 11C around a rotation shaft 13R extending in the vehicle width direction, and a middle leaf rear disposed in front of the rotation shaft 13R. An end receiving portion (third abutting portion) 15R and a rear leaf front end receiving portion (second abutting portion) 16F disposed behind the rotating shaft 13R are integrally provided.

  The front end portion of the front leaf spring 8F comes into contact with the front leaf front end receiving portion 14F fixed to the main beam 3 at the upper portion of the first hanger 11A from below, and the rear end portion thereof is the front leaf of the front equalizer 12F. It contacts the rear end receiving portion 14R from below. The front end portion of the middle leaf spring 8M is in contact with the middle leaf front end receiving portion 15F of the front equalizer 12F from below, and the rear end thereof is in contact with the middle leaf rear end receiving portion 15R of the rear equalizer 12R from below. The front end portion of the rear leaf spring 8R is in contact with the rear leaf front end receiving portion 16F of the rear equalizer 12R from below, and the rear end portion thereof is a rear leaf rear end receiving portion (first end) held at a lift prohibition position described later. Abutting part) 16R from below.

  In this way, the intermediate portion of the front leaf spring 8F is connected to the rear front shaft 6F, the front leaf front end receiving portion 14F on the vehicle body side is placed on the front end portion of the front leaf spring 8F, and the rear end portion of the front leaf spring 8F is placed. The vehicle body side load is elastically supported through the front leaf spring 8F by the rear front shaft 6F of the grounded rear front wheel 5F in a suspended state in which the vehicle body side front leaf rear end receiving portion 14R is placed on the ground. Similarly, the middle portion of the middle leaf spring 8M is connected to the rear middle shaft 6M, the middle leaf front end receiving portion 15F on the vehicle body side is placed on the front end portion of the middle leaf spring 8M, and the vehicle body is placed on the rear end portion of the middle leaf spring 8M. The vehicle body side load is elastically supported via the middle leaf spring 8M by the rear middle shaft 6M of the middle wheel 5M after being grounded in the suspended state where the middle middle leaf rear end receiving portion 15R is placed. Further, an intermediate portion of the rear leaf spring 8R is connected to the rear rear shaft 6R, a rear leaf front end receiving portion 16F on the vehicle body side is placed on the front end portion of the rear leaf spring 8R, and a rear end portion is mounted on the rear end portion of the rear leaf spring 8R. The vehicle body side load is elastically supported via the rear leaf spring 8R by the rear rear shaft 6R of the grounded rear rear wheel 5R in a suspended state where the leaf rear end receiving portion 16R is placed.

  A front end portion of the front radius rod 17F is rotatably connected to the lower end portion of the first hanger 11A, and a rear end portion of the front radius rod 17F is rotatably connected to a lower portion of the front end of the front shaft connecting member 10F. The front end of the middle radius rod 17M is rotatably connected to the lower end of the second hanger 11B, and the rear end of the middle radius rod 17M is rotatably connected to the lower front end of the middle shaft connecting member 10M. A front end portion of the rear radius rod 17R is rotatably connected to a lower end portion of the third hanger 11C, and a rear end portion of the rear radius rod 17R is rotatably connected to a lower portion of the front end of the rear shaft connecting member 10R.

  The front side equalizer 5F is tilted when the rear front wheel 5F and the rear middle wheel 5M pass through a step or the like and the load shared between the rear front shaft 6F and the rear middle shaft 6M changes. Thus, it has an equalizer function of maintaining the ground contact of the rear front wheel 5F and the rear middle wheel 5M. Similarly, when the rear middle wheel 5M and the rear rear wheel 5R pass through a step or the like, the rear equalizer mechanism 9R changes when the load shared between the rear middle shaft 6M and the rear rear shaft 6R changes. The equalizer 12R tilts and has an equalizer function of maintaining the ground contact between the rear middle wheel 5M and the rear rear wheel 5R.

  Next, the axle lift mechanism 20 will be described. The axle lift device 20 is equipped on the semi-trailer 1 to lift the rear rear wheel 5R from a state where all the wheels 5F, 5M, 5R are in contact with the ground, and a leaf receiving portion movable mechanism (first contact portion moving means) 21; An axle raising / lowering mechanism (axle raising / lowering means) 31, an equalizer fixing mechanism (tilt regulating means) 51, and an air circuit 71 are provided. The main components of the leaf receiving portion movable mechanism 21, the axle lifting mechanism 31, and the equalizer fixing mechanism 51 are provided on the left and right sides corresponding to the left and right rear rear wheels 5R, respectively.

  The leaf receiving portion movable mechanism 21 includes a leaf receiving link air cylinder 22, a drive-side leaf receiving link 23, a driven-side leaf receiving link 24, and a leaf receiving link rotating shaft 25. The cylinder tube 22a of the air cylinder 22 is fixed to a cross member 26 for fixing a leaf receiving cylinder that extends between the left and right main beams 3 and extends in the vehicle width direction. The piston rod 22b of the air cylinder 22 is fixed to the cylinder tube 22a. It can be extended forward from the front. The rotating shaft 25 extends in the vehicle width direction, and both end portions thereof are rotatably supported by the left and right fourth hangers 11D. An upper end portion of the leaf receiving link 23 is rotatably connected to a front end portion of the piston rod 22 b, and a lower end portion thereof is fixed to the rotating shaft 25. The upper end portion of the leaf receiving link 24 is fixed to the rotary shaft 25, and the rear leaf rear end receiving portion 16R is fixed to the lower end portion thereof. The rotating shaft 25 is shared by the left and right leaf receiving part moving mechanisms 21.

  The air cylinder 22 is set to a lift prohibition state (see FIGS. 1, 2, 7, 8, and 10) in which the piston rod 22b extends most and a lift permission state (see FIGS. 11 to 14) in which the piston rod 22b extends most. The leaf receiving link 23 and the leaf receiving link 24 rotate integrally with the rotating shaft 25 according to the expansion and contraction of the piston rod 22b, and the rear leaf rear end receiving portion 16R moves. In the lift prohibited state, the rear leaf rear end receiving portion 16R is held in a suspended lift prohibited position that abuts the rear end portion of the rear leaf spring 8R from above and restricts the upward movement of the rear end portion. . When the piston rod 22b is shortened from the lift prohibited state, the rear leaf rear end receiving portion 16R moves forward and obliquely upward by the rotation of the rotary shaft 25. In the lift permitted state, the rear leaf spring 8R is suspended from the suspended state. The lift is allowed to be lifted at a position allowing the lift.

  Fixed to the fourth hanger 11D is a flat plate-like lower link abutting portion 27 that abuts (surface contact) from behind the leaf receiving link 24 in a lift prohibited state. The front surface portion of the lower link contact portion 27 that contacts the leaf receiving link 24 is directed upward so as to share and support a part of the load input from the rear leaf rear end receiving portion 16R to the rotary shaft 25. It extends obliquely forward. The lower end portion of the leaf receiving link 24 (rear leaf rear end receiving portion 16R) is a leaf receiving link that is rotatably supported on the rotating shaft 25 according to the change from the lift permission state to the lift prohibition state. The upper end portion of the rotation shaft 25 moves from the front of the rotary shaft 25 to the rear and moves to the rear, contacts the lower link contact portion 27, and is set to the lift prohibited position. Therefore, when an upward load is input from the rear end portion of the rear leaf spring 8R to the rear leaf rear end receiving portion 16R, the leaf receiving link 24 is in a direction opposite to the lift permission position (lift permitted state). It is going to tilt toward the lower link contact part 27 of the back which is. Accordingly, the upper load input from the rear end portion of the rear leaf spring 8R to the rear leaf rear end receiving portion 16R is received by the lower link contact portion 27, and the rear leaf rear end receiving portion 16R is moved from the lift prohibition position. It is possible to reliably prevent the movement to the lift permission position.

  The axle lifting mechanism 31 includes a lift air cylinder 32, a roller chain 33, a drive side sprocket 34, an intermediate sprocket 35, a driven side sprocket 36, and a chain tensioner 37. The cylinder tube 32a of the air cylinder 32 is fixed to a lift cylinder fixing cross member 38 extending between the left and right main beams 3 in front of the leaf receiving cylinder fixing cross member 26 and extending in the vehicle width direction. The piston rod 32b of the cylinder 32 can extend forward from the cylinder tube 32a.

  A cross member 60 for fixing an equalizer cylinder extending in the vehicle width direction is installed between the left and right main beams 3 in front of the cross member 38 for fixing the lift cylinder, and between these cross members 38 and 59. A drive-side sprocket support center member 39 extending in the front-rear direction is provided at the approximate center of the left and right main beams 3. A center portion of a drive side sprocket support member 40 extending in the vehicle width direction is supported by the center member 39 so as to be slidable in the front-rear direction, and left and right lift air is provided at left and right ends of the drive side sprocket support member 40. The front end portion of the piston rod 32b of the cylinder 32 is fixed.

  The drive side sprocket 34 is supported by the drive side sprocket support member 40 so as to be rotatable about a rotation shaft extending in the vehicle width direction. The intermediate sprocket 35 is supported at the corner of the rear upper end of the bracket 41 fixed to the rear surface of the cross member 38 so as to be rotatable about a rotation axis extending in the vehicle width direction. The driven-side sprocket 36 is supported by the rear shaft coupling member 10R above the rear rear shaft 6R so as to be rotatable about a rotation shaft extending in the vehicle width direction. One end of the roller chain 33 is fixed to the front part of the bracket 41, extends forward through the lower part of the lift air cylinder 32, meshes with the range from the lower end part of the drive side sprocket 34 to the upper end part, and is folded back. It extends rearward through the upper part of the lift air cylinder 32, meshes with the range from the upper end of the intermediate sprocket 35 to the rear end, extends downward, and meshes with the range from the rear end to the front end of the driven sprocket 36. The other end is fixed to the rear portion of the bracket 41.

  The chain tensioner 37 is an elastic annular body having an outer periphery that can mesh with the roller chain 33, and is disposed between the front and rear roller chains 33 that extend in the vertical direction opposite to each other between the bracket 41 and the driven sprocket 36. The The outer diameter of the chain tensioner 37 is larger than the distance between the front and rear roller chains 33, and meshes in a state of being sandwiched between the front and rear roller chains 33 while being elastically deformed in an elliptical shape. A desired tension is applied to the roller chain 33 by the elastically deformed chain tensioner 37 pressing in the direction of separating the front and rear roller chains 33.

  The air cylinder 32 can be set to a non-lifted state (see FIGS. 1, 2, 8, 10, and 11) in which the piston rod 32b is shortened most and a lifted state (see FIGS. 12 and 14) in which it is extended most. In accordance with the expansion and contraction of the piston rod 32b, the driving side sprocket 34 moves in the front-rear direction, the roller chain 33 moves, and the driven side sprocket 36 (rear rear shaft 6R) moves up and down.

  In front of the drive-side sprocket support member 40, a lowering prevention stopper member 42 is provided for maintaining the lift state of the axle lifting mechanism 31 and preventing the rear rear shaft 6R from lowering. The descent prevention stopper member 42 is a rod-shaped body that extends in the vehicle width direction, and has one end (right end) and a center that are rotatably supported by the center member 39 and the left main beam 3, respectively. (Left end side) extends outward in the vehicle width direction of the left main beam 3. The drive side sprocket support member 40 is provided with an engagement hole 43. One end of the lowering prevention stopper member 42 is driven in accordance with a rotation operation of the lowering prevention stopper member 42 in a lift state in which the piston rod b extends most. A locking projection 44 that is detachably engaged with the engagement hole 43 of the side sprocket support member 40 is provided (see FIG. 8). The engagement of the engagement hole 43 and the locking projection 44 prevents the drive side sprocket support member 40 from moving backward, and the lift state of the axle lifting mechanism 31 is maintained.

  The equalizer riser fixing mechanism 51 includes an equalizer cylinder air cylinder 52, first to third links 53 to 55, front and rear tilt restricting links 56 and 57, and front and rear equalizer rise rotating shafts 58 and 59. A cylinder tube 52a of the air cylinder 52 is fixed to the above-described cross member 60 for fixing the equalizer cylinder, and a piston rod 52b of the air cylinder 52 can be extended rearward from the cylinder tube 52a. The front rotary shaft 58 extends in the vehicle width direction in front of the third hanger 11C, and both ends thereof are rotatably supported by bearings 61 (see FIG. 2) fixed to the lower surfaces of the left and right main beams 3. (See FIG. 7). The rear rotating shaft 59 extends in the vehicle width direction behind the third hanger 11C, and the left and right rotating shafts 59 are rotatable on bearings 62 (see FIG. 2) fixed to the lower surfaces of the left and right main beams 3, respectively. (See FIG. 7). The upper end portion of the first link 53 is rotatably connected to the rear end portion of the piston rod 52b, and the lower end portion thereof is fixed to the front rotating shaft 58. The upper end portion of the third link 55 is fixed to the rear rotating shaft 59, and the front end portion and the rear end portion of the second link 54 are respectively connected to the intermediate portion of the first link 53 and the lower end portion of the third link 55. It is connected rotatably. The front and rear tilt restriction links 56 have their upper ends fixed to the front rotary shaft 58 and extend downward. The rear tilt restriction link 57 has an upper end fixed to the rear rotation shaft 59 and extends downward. The front rotary shaft 58 is shared by the left and right equalizer fixing mechanisms 51.

  The air cylinder 52 can be set to a tilt allowable state in which the piston rod 52b extends most (see FIGS. 1, 2, 7, and 10) and a tilt restriction state in which the piston rod 52b shortens most (FIGS. 11 to 13). According to the expansion and contraction of the piston rod 52b, the front and rear rotating shafts 58 and 59 rotate in opposite directions, and the front and rear tilt restriction links 56 and 57 move. In the tilt permission state, the lower end portions of the front and rear tilt restriction links 56 and 57 are held at a tilt permission position that is spaced upward from the upper surface of the rear equalizer 12R to allow the equalizer 12R to tilt. When the piston rod 52b is shortened from the tilt-permitted state, the lower end portion of the front tilt restriction link 56 moves rearward and obliquely downward by the rotation of the front rotation shaft 58, and the lower end portion of the rear tilt restriction link 57 is moved to the rear side. The rotary shaft 59 moves obliquely downward in the forward direction. In the tilt regulation state, the lower end portions of the front and rear tilt regulation links 56 and 57 are held at a tilt regulation position that regulates the tilt of the equalizer 12R by approaching or contacting the upper surface of the equalizer 12R before and after the rotating shaft 13R.

  The lower end portion of the front tilt restriction link 56 rotates from the front of the rotating shaft 58 (the upper end portion of the tilt restriction link 56 that is rotatably supported on the vehicle body side) in accordance with the change from the tilt permission state to the tilt restriction state. It moves rearward beyond the vertical lower side of the shaft 58 and approaches or contacts the upper surface of the equalizer 12R in front of the rotating shaft 13R. The lower end portion of the rear side tilt restricting link 57 is rearward of the rotating shaft 59 (the upper end portion of the tilt restricting link 57 supported rotatably on the vehicle body side) in accordance with the change from the tilt permitting state to the tilt restricting state. It moves forward beyond the vertically lower side of the rotating shaft 59 and approaches or contacts the upper surface of the equalizer 12R behind the rotating shaft 13R. The tilt of the equalizer 12R is regulated by the upper surface of the equalizer 12R coming into contact with the lower end portion of the front tilt regulating link 56 and / or the lower end portion of the rear tilt regulating link 57. For this reason, even when a strong tilting force acts on the equalizer 12R from the rear end portion of the middle leaf spring 8M or the front end portion of the rear leaf spring 8R in the tilt regulation state, the front side receives the tilt of the equalizer 12R. Since the direction in which the tilt restriction link 56 or the rear side tilt restriction link 57 tries to tilt is opposite to the tilt release state, the tilt prohibition state can be reliably maintained.

  As shown in FIG. 9, the air circuit 71 includes a main pipeline 72 communicating with an air tank (not shown) that stores pressurized air, first to third branch pipelines 73 </ b> A to 73 </ b> C branched from the main pipeline 72, The first to third manual operation valves 74A to 74C connected to the downstream ends of the first to third branch pipes 73A to 73C, the first manual operation valve 74A, and the left and right leaf receiving link air cylinders 22 respectively. A first extension side pipe 75A communicating with the extension side of the cylinder chamber, a first shortening side pipe connecting the first manual operation valve 74A and the shortening side of each cylinder chamber of the left and right leaf receiving link air cylinders 22 A second extension side conduit 76A that communicates the passage 75B, the second manual operation valve 74B, and the extension side of each cylinder chamber of the left and right lift air cylinders 32; the second manual operation valve 74B and the left and right lift air; Each cylinder chamber of the cylinder 32 A second shortening side conduit 76B that communicates with the shortening side, a third extension side conduit 77A that communicates between the third manual operation valve 74C and the extension side of each cylinder chamber of the right and left ecolyzer link air cylinders 52; The second manual operation valve 74C and the second shortened side pipe line 77B communicating the shortened sides of the cylinder chambers of the right and left ecolyzer link air cylinders 52 are provided.

  The first to third manual operation valves 74A to 74C can be set to a three-axis traveling state (non-lift state) and a two-axis traveling state (lift state), respectively, by manual operation from a driver or the like.

  The first manual operation valve 74A in the three-axis traveling state communicates the first branch pipe 73A and the first extension pipe 75A, and opens the first shortening pipe 75B to the atmosphere. As a result, the piston rod 22b extends, and the lift is prohibited. The first manual operation valve 74A in the biaxial traveling state communicates the first branch pipe 73A and the first shortened pipe 75B, and opens the first extension pipe 75A to the atmosphere. Thereby, piston rod 22b shortens and it will be in a lift permission state.

  The second manually operated valve 74B in the three-axis traveling state communicates the second branch conduit 73B and the second shortened conduit 76B, and opens the second extension conduit 76A to the atmosphere. Thereby, piston rod 32b shortens and it will be in a non-lift state. The second manual operation valve 74B in the biaxial traveling state communicates the second branch conduit 73B and the second extension side conduit 76A, and opens the second shortened side conduit 76B to the atmosphere. As a result, the piston rod 32b extends and enters a lift state.

  The third manual operation valve 74C in the three-axis traveling state communicates the third branch pipe 73C and the third extension pipe 77A, and opens the third shortening pipe 77B to the atmosphere. As a result, the piston rod 52b extends, and the tilt is allowed. The third manual operation valve 74C in the biaxial traveling state communicates the third branch conduit 73C and the third shortened conduit 77B, and opens the third extension conduit 77A to the atmosphere. Thereby, the piston rod 52b shortens and it will be in a tilt control state.

  When the three-axis traveling is performed with the three wheels including the rear front wheel 5F, the rear middle wheel 5M, and the rear rear wheel 5R, the first to third manual operation valves 74A to 74C are set to the three-axis traveling state, respectively. As shown in FIG. 2, the leaf receiving portion movable mechanism 21 is maintained in a lift prohibited state, the axle lifting mechanism 31 is maintained in a non-lift state, and the equalizer fixing mechanism 51 is maintained in a tilting permitted state. The rear leaf rear end receiving portion 16R of the leaf receiving portion movable mechanism 21 in the lift prohibited state is held at the lift prohibited position, and comes into contact with the rear end portion of the rear leaf spring 8R from above to move upward of the rear end portion. Therefore, the load on the vehicle body side is elastically supported via the rear leaf spring 8R by the rear rear shaft 6R of the rear rear wheel 5R that is grounded. Further, the lower end portions of the front and rear tilt regulating links 56 and 57 of the ecologicalizer fixing mechanism 51 in the tilting permitted state are held at the tilting allowable position and are spaced upward from the upper surface of the rear ecolyzer 12R. The 9M equalizer function works effectively.

  When changing from 3-axis travel to 2-axis travel (travel with the rear rear wheel 5R lifted), the driver or the like moves the third manual operation valve 74C from the 3-axis travel state to the 2-axis travel state while the vehicle 1 is stopped. Switch to. When the third manual operation valve 74C is switched to the biaxial running state, the equalizer riser fixing mechanism 51 shifts from the tilting allowable state to the tilting restricting state, and the lower end portions of the front and rear tilting restricting links 56 and 57 tilt from the tilting allowable position. It descends to the restriction position, and approaches or contacts the upper surface of the equalizer 12R before and after the rotating shaft 13R to restrict the tilting of the equalizer 12R (see FIG. 10).

  Next, the driver or the like switches the first manual operation valve 74A to the biaxial traveling state. When the first manual operation valve 74A is switched to the biaxial traveling state, the leaf receiving portion movable mechanism 21 shifts from the lift prohibition state to the lift permission state, and the rear leaf rear end receiving portion 16R changes from the lift prohibition position to the lift permission position. (See FIG. 11), allowing the rear end of the rear leaf spring 8R to rise from the suspended state.

  Next, the driver or the like switches the second manual operation valve 74B to the biaxial traveling state. When the second manual operation valve 74B is switched to the biaxial traveling state, the axle lifting mechanism 31 shifts from the non-lift state to the lift state, the piston rod 32b of the lift air cylinder 32 extends, and the roller chain 33 moves. Then, the rear radius rod 17R tilts forward and obliquely upward about the front end portion (the connecting shaft between the third humber 11C and the rear radius rod 17R), and the rear rear shaft 6R (rear rear wheel 5R) rises (see FIG. 12). ).

  After the axle lifting mechanism 31 has completely shifted to the lifted state, the driver or the like rotates the other end portion (left end portion) of the lowering prevention stopper member 42 and descends into the engagement hole 43 of the drive side sprocket support member 40. The locking protrusion 44 of the prevention stopper member 42 is engaged. The engagement of the engagement hole 43 and the locking projection 44 prevents the drive side sprocket support member 40 from moving backward, and the lift state of the axle lifting mechanism 31 is maintained.

  When returning from the 2-axis travel to the 3-axis travel, the driver or the like may operate the lowering prevention stopper member 42 and the manual operation valves 74A to 74C in the reverse order of the above.

  As described above, according to the present embodiment, the rear front wheel 5F, the rear middle wheel 5M, and the rear rear wheel 5R are changed from the three-axis traveling to the two-axis traveling in which the rear rear wheel 5R is lifted away from the ground. In this case, the driver or the like switches the third manual operation valve 74C to the biaxial traveling state to change the equalizer fixing mechanism 51 from the tilting permitted state to the tilting restricted state, and switches the first manual operation valve 74A to the biaxial traveling state. After the leaf receiving portion movable mechanism 21 is changed from the lift prohibited state to the lift permitted state, the second manual operation valve 74B is switched to the biaxial traveling state, and the rear rear shaft 6R is raised by the axle lifting mechanism 31.

  When the leaf receiving portion movable mechanism 21 shifts from the lift prohibition state to the lift permission state, the rear leaf rear end receiving portion 16R moves from the lift prohibition position to the lift permission position. As the rear leaf rear end receiving portion 16R moves to the lift prohibition position, the rear end of the rear leaf spring 8R is allowed to rise from the suspended state, so that the rear leaf spring 8R moves along with the rear rear shaft 6R. Tilt overall. Therefore, compared with the case where the rear rear shaft 6R is raised against the urging force of the rear leaf spring 8R, the force for raising the rear rear shaft 6R can be kept small, and the axle lift device 20 can be made larger. Weight increase can be suppressed. Further, since the movable range of the rear rear shaft 6R is not limited to the elastic deformation region of the rear leaf spring 8R, the rear rear wheel 5R can be sufficiently separated from the ground.

  Further, when the equalizer fixing mechanism 51 is changed to the tilt restriction state, the tilt of the equalizer 12R is restricted. Therefore, when the rear rear shaft 6R is raised by the axle lifting mechanism 31, the front end portion of the rear leaf spring 8R is The ascent is reliably suppressed by the lower end portion of the tilt restricting link 57. Accordingly, it is possible to raise the rear rear shaft 6R while reliably tilting the rear leaf spring 8R with a stable behavior.

  In addition, during the three-axis travel, the equalizer riser fixing mechanism 51 is set in the tilt permission state, so that the equalizer rises and the equalizer rises to function. Therefore, the load on the vehicle body side can be suitably distributed to the rear middle shaft 6M and the rear rear shaft 6R.

  The above-described embodiment is an example of the present invention, and the present invention is not limited to the above-described embodiment, and is not limited to the above-described embodiment as long as it does not depart from the technical idea according to the present invention. Of course, various modifications are possible.

  For example, in the above-described embodiment, the case of lifting the rear rear wheels 5R on the rear end side of the three sets of wheels 5F, 5M, 5R arranged in the front-rear direction has been described. One may be lifted, or the wheel on the front end side may be lifted.

  Instead of the air cylinders 22, 32, 52, other actuators such as a hydraulic cylinder and a motor may be provided. Moreover, it replaces with manual operation valve 74A-74C, an electromagnetic valve may be provided, and an electromagnetic valve may be controlled by switch operation etc.

1: Semi-trailer (vehicle)
2: Chassis frame 3: Main beam 5F: Rear front wheel 5M: Rear middle wheel (second wheel)
5R: Rear rear wheel (first wheel)
6F: Rear front shaft 6M: Rear middle shaft 6R: Rear rear shaft 7: Suspension device 8F: Front leaf spring 8M: Middle leaf spring 8R: Rear leaf springs 9F, 9R: Front and rear ecolyzer mechanisms 12F, 12R: Equalizer 14F: Front leaf Front end receiving portion 14R: front leaf rear end receiving portion 15F: middle leaf front end receiving portion (fourth contact portion)
15R: Middle leaf rear end receiving portion (third contact portion)
16F: Rear leaf front end receiving portion (second contact portion)
16R: Rear leaf rear end receiving portion (first contact portion)
20: Axle lift device 21: Leaf receiving portion moving mechanism (first contact portion moving means)
22: Leaf receiving link air cylinder 23: Leaf receiving link 24: Leaf receiving link 25: Leaf receiving link rotating shaft 27: Lower link contact portion 31: Axle lifting mechanism (axle lifting means)
32: Lifting air cylinder 33: Roller chain 34: Drive side sprocket 35: Intermediate sprocket 36: Driven side sprocket 37: Chain tensioner 42: Lowering prevention stopper member 51: Equalizer fixing mechanism (tilt regulating means)
52: Air cylinder 53-55 for ecolyzer link: First to third links 56, 57: Front and rear tilt restriction links 58, 59: Front and rear eco-riser fixing rotating shaft 71: Air circuit

Claims (2)

A vehicle including first and second wheels arranged in the front-rear direction and a suspension device, wherein the suspension device includes a leaf spring, and an intermediate portion in the front-rear direction of the leaf spring is connected to an axle of the first wheel. In a suspended state in which the first contact portion on the vehicle body side is placed on one end portion in the front-rear direction of the leaf spring and the second contact portion on the vehicle body side is placed on the other end portion in the front-rear direction of the leaf spring. The first wheel is lifted from the state in which the first and second wheels are grounded to the vehicle in which the load on the vehicle body is elastically supported via the leaf spring by the grounded axle of the first wheel. Axle lift device equipped for
A first contact portion moving means supported on the vehicle body side and settable in a lift prohibited state and a lift permitted state;
Axle lifting means supported on the vehicle body side and capable of raising and lowering the axle of the first wheel,
In the lift prohibited state, the first contact portion moving means contacts the one end portion of the leaf spring from above and restricts the upward movement of the one end portion to the lift prohibited position in the suspended state. A vehicle that holds one abutting portion and moves the first abutting portion to a lift permitting position that allows the one end of the leaf spring to lift from the suspended state in the lift permitting state. Axle lift device. The axle lift device according to claim 1,
Tilt restricting means that can be set in a tilt permitting state and a tilt restricting state,
The leaf suspension device includes a second leaf spring and an equalizer mechanism,
An intermediate portion in the front-rear direction of the second leaf spring is connected to an axle of the second wheel, and a vehicle body is attached to one end portion in the front-rear direction of the second leaf spring extending from the intermediate portion to the first wheel side. Of the second wheel grounded in a suspended state in which the third contact portion on the side is placed and the fourth contact portion on the vehicle body side is placed on the other end portion in the front-rear direction of the second leaf spring. The vehicle body side load is elastically supported by the axle via the second leaf spring,
The equalizer mechanism is supported on the vehicle body side so as to be tiltable about a rotation shaft extending in a vehicle width direction between the other end portion of the leaf spring and the one end portion of the second leaf spring, and the rotation shaft A tilting member in which the second contact portion is provided on the first wheel side, and the third contact portion is provided on the second wheel side with respect to the rotating shaft,
The vehicle axle lift device according to claim 1, wherein the tilt restricting means permits tilting of the tilting member in the tilt permitting state, and restricts tilting of the tilting member in the tilt restricting state.

Images