JP2008223480A - Asphalt finisher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a vibration load imposed on a screed man which is boarding a step of an asphalt finisher. <P>SOLUTION: The step 20 is provided to a support member of a frame through the medium of a shock-absorbing device, and the frame has a base plate which applies vibration to a plied timber and pushes it which is provided to a screed. The shock-absorbing device has a rubber damper 56, a spring 58, and compression means 59, 62 of the spring. The spring has been compressed by a compression means by the length bent by the weight of the step and the weight of the screed man. In a state where the spring has been compressed in advance, there is no or small compression bending in the rubber damper of the asphalt finisher so that the damping force of the rubber damper is acted in the vibration process above the step. The rubber damper works in the up-and-down directions. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an asphalt finisher provided with a step of performing asphalt pavement construction, and particularly preferably relates to an asphalt finisher further provided with a tamper device.

  The asphalt pavement road is composed of a plurality of asphalt layers in which asphalt pavements are constructed in several layers. Asphalt pavement consists of a layer of a mixture of natural sand, gravel, crushed stone and other aggregates mixed with straight asphalt, and asphalt pavement is a solidified mixture.

    The asphalt finisher is transported from a contractor base to a construction site by a trailer or a truck. At the construction site, the asphalt finisher takes charge of the process of mixing at the asphalt mixture plant and laying and leveling the mixture transported to the construction site by trucks and dump trucks. The mixed material is directly delivered from the truck or dump truck to the asphalt finisher, spread to the width of the asphalt pavement, and pressed against the lower roadbed and laid.

  On normal asphalt paved roads, rainwater does not soak into the road, so a water film is formed between the tires of the passing car and the road surface, causing a brake to become ineffective (hydroplaning phenomenon). In recent years, drainage paved roads called high-standard roads have been adopted on highways and main roads. In addition to eliminating the hydroplaning phenomenon, the drainage paved road is said to have an effect of preventing the driver's view from deteriorating due to water splashing, and also to reduce noise.

  In the drainage paved road, the rainwater soaked in the surface layer flows on the base layer below and is collected in the drainage ditch. At this time, the surface layer infiltrated with rainwater is constructed with a mixture of asphalt mixed with sand and stone powder, which is slightly coarser than normal pavement, and added with rubber and resin to increase adhesion. . As a result, a surface layer having innumerable communicating voids through which rainwater passes can be formed. Therefore, rainwater that has fallen on the road surface passes through the surface layer in a short time, and therefore cannot accumulate on the road surface.

In the drainage paved road, for example, asphalt is mixed with aggregate composed of a particle size of 13 to 5 millimeters (No. 6 crushed stone), medium sand and stone powder, and used as a composite material. The crushed stone in the above has a particle size larger than the crushed stone of the pavement material used for a normal paved road. Use more tar asphalt to bind crushed stone with larger particle size. In addition, a tamper device is used because crushed stone cannot be hardened even if it is spread only with the base plate of the asphalt finisher. The tamper device is provided with drive means for moving the tamper edge up and down to ground the composite material by grounding it. The tamper edge is between a strike-off in front of the tamper edge in the traveling direction of the asphalt finisher and a screed base plate (hereinafter simply referred to as a base plate) in the rear.
JP 2002-302907 A JP 2003-213617 A JP 2003-221806 A JP 2005-248576 A JP 2005-2458577 A JP 2005-248578 A JP 2005-248579 A

    Asphalt finishers are provided with a step for boarding a screed man at the rear end in the direction of travel. The base plate not only presses the compound material but also vibrates and presses at the same time. In order to apply this vibration to the base plate, a vibration device is provided in the frame above the base plate. Since the step is supported by this frame, the step vibrates.

    In an asphalt finisher equipped with a tamper device, vibration is applied based on the tamper device. The step therefore vibrates.

    Even if the latter vibration is reduced, it is possible to reduce the vibration based on the vibrating device by vibrating only the base plate, but such a method has not been developed at present.

    The asphalt finisher includes a vibration device in the screed device. For this reason, the screed of the asphalt finisher vibrates. Workers on the asphalt finisher are constantly receiving vibration from the asphalt finisher during work. The above workers manage the pavement thickness in a standing position on the screw. As a result, the feet and the waist are always subjected to the vibration. It is known to hurt the knees and lower back.

    An asphalt finisher equipped with a tamper device vibrates more intensely than an asphalt finisher without a tamper device. Therefore, considering the health of workers, for example, the workplace is rearranged with the driving history of asphalt finishers within 10 years.

    Conventionally, it has been considered that an asphalt finisher equipped with a tamper device has a larger vibration than an asphalt finisher without a tamper device because the tamper moves in the vertical direction and strikes and mixes the mixture.

An object of the present invention is to provide an asphalt finisher having a step in which vibration is greatly reduced.

The first invention according to the present application is an asphalt finisher for performing asphalt pavement construction.
A traveling device for traveling an asphalt finisher;
A composite material transporting device for transporting the composite material from the hopper at the front of the vehicle to the rear of the vehicle;
Screw blades that spread the composite material to the width of asphalt pavement,
A screed equipped with a vibration device and vibrated and pressed against the surface on which the composite material is to be constructed,
A step for boarding a screed man provided at the rear end of the screed;
Have
The step is provided via a shock absorber on a support member of a frame having a base plate that vibrates and presses the composite material provided on the screed, and the shock absorber includes a rubber damper, a spring and a spring compression means, The spring is compressed in advance by the compression means by the weight of the step and the length of the screedman by the weight of the screedman. When the spring is pre-compressed, the damping force of the rubber damper acts in the vibration process upward of the step. Thus, the rubber damper is an asphalt finisher characterized in that it has no compression deflection or small compression deflection.

A second invention according to the present application is the asphalt finisher according to the first invention, which includes a tamper device.

The step is provided via a shock absorber on a support member of a frame having a base plate that vibrates and presses the composite material provided on the screed, and the shock absorber includes a rubber damper, a spring and a spring compression means, The spring is compressed in advance by the compression means by the weight of the step and the length of the screedman by the weight of the screedman. When the spring is pre-compressed, the damping force of the rubber damper acts in the vibration process upward of the step. As described above, since the rubber damper has no compression deflection or has a small compression deflection, the vibration component of the vertical movement is attenuated by the rubber damper in both the reciprocating motion, and the vibration of the step can be suppressed. In particular, it is effective not only for an asphalt finisher having a tamper device, but also for an asphalt finisher without a tamper device.

Embodiments of the present invention will be described below with reference to the drawings. The description will be given first of the embodiment of the main body of the asphalt finisher having the tamper device of the application example of the present invention, and finally the embodiment of the present invention.

  In the following description, the left and right are the left and right as viewed in the direction of travel of the asphalt finisher. The front-rear direction refers to the same direction as the asphalt finisher travels.

(overall structure)
6 and 7 are a side view and a plan view of the asphalt finisher. The chassis frame 1 is supported by four wheels 2 and travels in the direction of arrow A with an internal combustion engine (not shown). That is, the asphalt finisher as a vehicle has a traveling device. In addition, there exists a thing by a crawler as a traveling apparatus.

    A screed device 5 is provided at the end of the arm 4 whose root is coupled to the chassis frame 1 by a pin 3. The ends of the arms 4 on both sides are joined by a horizontal member, and a fixed shaft 7 is provided across the arms. A central screed frame 8 is rotatably supported on the fixed shaft 7. The central screed frame 8 is tilted by the operation handle 9.

    A central screed 11 is fixed to a frame member extending to the left and right of the central screed frame 8. A widener support frame 12 is fixed to the central screed frame 8. A widener frame 13 is attached to the widener support frame 12 so as to be extendable in the left and right sides. The widener frame 13 is provided with a circular hole as a guide in the horizontal direction, and the guide bar 14 of the guide member is fitted into the circular hole so as to freely slide in and out. The widener frame 13 is fitted to the tip of the guide bar 14. Is fixed. A widener screed 15 is supported on the widener frame 13.

    The central screed 11 is in front of the widener screed 15 in the vehicle traveling direction, and both end portions always overlap. The lower surfaces of the widener screed 15 and the central screed 11 are on the same plane. Note that some asphalt finishers do not have a widener screed, but the tamper device described below is also applied to a case without a widener screed.

    Although not shown, the screed device 5 includes a vibration device (not shown) for exciting the base plate portions of the screeds 11 and 15. Moreover, the heating means for heating the baseplate part of both the screeds 11 and 15 is provided.

    At the time of work, the vehicle is moved forward, the arm 4 is rotated around the pin 3 with the hydraulic device not described, and the screed device 5 is lowered to a position where it becomes a required paved surface, and the hopper 17 provided at the front part of the vehicle is placed. When asphalt composite material (hereinafter referred to as composite material) is introduced, it is sent to a screw blade 19 disposed at the rear of the vehicle by a conveyor 18 that moves in the direction of the arrow B shown in the figure, and by a screw blade 19 disposed at a right angle to the vehicle traveling direction. It is sent to both the left and right sides, sprayed on the roadbed, pushed by the central screed 11 and the widener screed 15 as the asphalt finisher advances, and is vibrated and heated and pressed by these lower surfaces. In the present invention, a tamper device, which will be described later, is provided, and at the same time, compaction of the mixture is performed.

    Steps 10 and 20 on which the screed man rides are provided at the rear end when viewed in the traveling direction of the asphalt finisher.

(Widener)
It is the widener screed 15 that determines the width of the asphalt finisher to construct the asphalt pavement. The screed that spreads and mixes the composite material is composed of a central screed 11 that is the basis of the width to be constructed, and a widener screed 15 that adjusts the width to be constructed.

  The widener screed 15 constitutes the left and right wings of the screed with respect to the traveling direction of the asphalt finisher indicated by the arrow A, and constitutes the screed together with the central screed 11.

    The widener screed 15 always has an overlap when viewed in the front-rear direction of the vehicle body while maintaining a certain clearance from the central screed 11.

(Screed device)
As already described, the screed device 5 includes the central screed 11 and the widener screed 15. 1 is a longitudinal sectional view of a central screed 11, FIG. 2 is a longitudinal sectional view of a widener screed, and FIG. 3 is a front view of the widener screed. FIG. 2 is also used to explain the central screed.

    As shown in FIGS. 1 and 2, the central screed 11 and the widener screed 15 mainly have a strike-off 21, a tamper device 22, a base plate 23, and a pressurizing device 24. The tamper device 22 has the same configuration as the central screed 11 and the widener screed 15 except for the drive source side of the drive means (drive device).

    The base plate 23 is fixed to the lower end of the frame 23A. Here, the frame 23A is integrally provided by a front plate 23e constituting the peripheral wall of the combustion chamber 23b, a member including the top plate 23c, and an upper plate 23f provided at the upper end of the front plate 23e extending upward. The frame 23A is solid on the central screed frame 8 or the widener frame 13.

    The lower surface 23a of the base plate 23 is a ground contact surface in contact with the composite material. The base plate 23 is heated by a heat source (not shown) to heat the base plate 23 over the entire width of each of the center screed 11 and the widener screed 15 (here, the width means a length perpendicular to the traveling direction of the asphalt finisher, the same applies hereinafter). A combustion chamber 23 b into which the heated air is sent is provided on the base plate 23. The combustion chamber 23 b extends over almost the entire width of the base plate 23. A vibration device (not shown) is provided on the top plate 23c constituting the combustion chamber 23b. The base plate portion 23a is heated to about 120 ° C. by the heated air sent into the combustion chamber 23b. In addition, the tamper device 22 and the strike-off 21 are heated by heat conduction. The mixed material is spread and spread by the asphalt finisher in the direction of the arrow A in the state of being pressed by the lower surface 23a of the vibrating base plate 23. The lower surface 23a has a front rising slope 23a1 at the front end for receiving the composite material, but is flat except for this.

    A tamper edge contact surface 23 d is provided at the front portion of the base plate 23. The tamper edge contact surface 23d is always in pressure contact with the rear contact surface 25c of the tamper edge 25 by the action of a tamper edge pressurizing device 24 described later.

    The upper part of the front plate 23e rises almost vertically as it is and is connected to the upper plate 23f in the horizontal direction. Then, both end portions of the frame 23A having the base plate 23 serving as the end portion of the screed width are side plates 23g. The base plate 23 is a thick steel plate fixed to a flange 23k provided with a bolt 30 on a constituent material of the combustion chamber 23b.

(Tamper device)
The tamper device 22 includes a tamper edge 25, a tamper bar 26 to which the tamper edge 25 is integrally fixed with a bolt or the like, a connecting member 28 that is in contact with the top surface of the tamper bar 26 and fixed to the tamper bar 26 with a bolt 27, and a connecting member 28 as shown in FIG. An eccentric ring member 31 that is fixed to the eccentric ring member 31 by means of a bolt 29 and an eccentric shaft 33 that the pin portion 33b rotatably supports the eccentric ring member 31 via a bearing 32, and a journal portion 33a of the eccentric shaft 33 (see FIG. 3). Has a bearing bracket 34 that rotatably supports the bearing bracket 34. The bearing bracket 34 has a bearing (not shown) that rotatably supports the journal portion 33a. The pin portion 33b is eccentric with respect to the journal portion 33a by half the stroke of the tamper edge 25.

    As shown in the figure, the tamper edge 25 has a square cross section, and the grounding surface in contact with the composite material is inclined so as to accept the horizontal lower surface 25b and the composite material in the traveling direction of the asphalt finisher in order to crush the composite material. It has a slope 25a. The tamper edge 25 is obtained by quenching ultra high strength steel. The cross-sectional dimension is about 25 millimeters in thickness in the front-rear direction and about 22 millimeters in height, and each of the screeds 11 and 15 has a length over the entire width.

    A tamper bar 26 having the same length as the tamper edge 25 is welded to the upper surface of the tamper edge 25. The tamper bar 26 has a thickness of 25 (−tolerance) millimeters and a height of 70 millimeters including the tamper edge 25. The tamper bar 26 enhances the strength and bending rigidity of the tamper edge 25 against a vertical load. At the same time, an inertia weight for compacting the composite material of the tamper edge 25 is obtained. The tamper bar 26 is a normal steel material. The tamper bar 26 has a thickness in the front-rear direction slightly smaller than the thickness of the tamper edge 25. The tamper bar 26 does not contact the tamper edge contact surface 23d of the base plate 23 and the strike-off tamper resistant edge contact surface 21f.

    As shown in FIG. 2, the connecting member 28 is in contact with the upper surface of the tamper bar 26, and is attached to the upper and lower sides of an angle member 28 a fixed to the tamper bar 26 with hexagon bolts 27, and a horizontal sectional square fixed to the angle member 28 a by welding. It has a long bar 28b.

    As shown in FIG. 3, the eccentric ring members 31 are disposed on both sides in the longitudinal direction of the frame 23A to which the base plate 23 is fixed. The eccentric shaft 33 rotatably supports the eccentric ring member 31 via a bearing 32 on a pin portion 33b eccentric from the journal portion 33a.

    The bearing bracket 34 is fixed to the frame 23A so that its vertical position can be adjusted. A device for this purpose is provided in the front plate 23e, which is guided by a guide (not shown) in the vertical direction, the lower end is screwed and fixed to the upper end of the bracket main body 34a, and the upper end is fixed to the upper plate 23f above the base plate 23. A through screw 35a for inserting the bracket 23h, nuts 35c and 35d screwed into the through screw 35a and holding the bracket 23h, and a long hole 34a1 extending vertically in the bracket body 34a are inserted into the front plate 23e. It has a bolt 34e.

    The bracket body 34a moves up and down by loosening the bolt 34e and changing the positions of the nuts 35c and 35d. Therefore, the tamper edge 25 integrated with the tamper bar 26 is moved up and down via the eccentric shaft 33, the bearing 32, the eccentric ring member 31, and the connecting member 28. Thus, the vertical position of the tamper edge 25 and the parallelism between the ground plane of the base plate 23 and the ground plane of the tamper edge 25 are adjusted. After the adjustment, the nuts 35c and 35d are fastened to the bracket 23h, and the bolt 34e is fastened.

(Strike off)
The strike-off 21 has an introduction portion 21a for introducing a necessary amount of the composite material, a receiving plate portion 21b for pushing the composite material in the forward direction of the asphalt finisher, and a substantially vertical front plate portion 21c. The introduction portion 21a is an inclined surface that slightly rises in the forward direction and serves as a ground surface. The receiving plate portion 21b is a vertical surface whose lower end side is slightly retracted from the upper end side in the forward direction. The crossing corner of the introduction part 21a and the attacking plate part 21b is rounded by an arc 21d. The rear end of the introduction portion 21a is a tamper edge contact surface 21f that contacts the front contact surface 25d of the tamper edge 25.

    The strike-off 21 is pivotally attached to the upper part of the frame 23A on the base plate 23 so as to be adjustable in position. Details will be described below.

    The strike-off 21 is pivotally attached to the frame 23A by a pin 36. The axis of the pin 36 is perpendicular to the traveling direction of the asphalt finisher and is horizontal. Pins 36 are respectively provided at both ends of the upper part behind the strike-off 21. The pin 36 can be adjusted in the front-rear direction on the bracket 37a of the support member 37 fixed to the upper back of the strike-off 21 so that the vertical position can be adjusted, and on the bracket 23i fixed to the upper plate 23f of the frame 23A ( The adjusting feeder is not fitted in the description), and is fitted in the respective holes of the support member 38 and the bracket 38a. The brackets 37a and 38a are perpendicular to each other and are in contact with each other.

    The support member 37 has an inverted L shape as shown in FIGS. An adjustment screw 39 in the vertical direction passing through a hole of the bracket 21 e provided at the upper part of the strike-off 21 is screwed into the horizontal piece 37 b of the support member 37. The bolt 40 is screwed and fixed to the strike-off 21 through an elongated hole 37 d provided in the vertical direction provided in the flange 37 c of the support member 37. Here, the adjusting screw 39 is, for example, a hexagon bolt.

    The strike-off 21 can be moved up and down by loosening the hexagon bolt 40 and rotating the adjusting screw 39. When the bolt 40 is tightened at a desired position, the vertical position of the strike-off 21 is determined. Since there are two adjustment bolts 39 in the width direction of the strike-off 21, the inclination of the introduction portion (grounding surface) 21 a in the width direction of the strike-off 21 can be adjusted.

    The support member 38 has a long hole 38b that is long in the front-rear direction. The support member 38 is fixed to the bracket 23i so that the bolt 41 passing through the long hole 38b is screwed into the bracket 23i and the position thereof can be adjusted in the front-rear direction. After loosening the bolt 41 and adjusting the position of the upper part of the strike-off 21 in the front-rear direction, the bolt 41 is tightened. As a result, the inclination of the strike-off 21 in the front-rear direction can be adjusted.

    Brackets 23i are provided in the vicinity of both ends in the longitudinal direction (width direction) of the frame 23A so that the front and rear positions of the support members 38 can be adjusted to the brackets 23i, so that the horizontal plane in the direction intersecting with the asphalt finisher traveling direction of the strike-off 21 The inclination inside can be adjusted. As a result, the anti-tamper edge contact surface 21f can be uniformly in contact with the front contact surface 25d of the tamper edge 25 in the longitudinal direction.

(Tamper device drive means)
The drive means of the tamper device 22 is rotated by transmitting the rotational force from the drive source to the journal portion 33a. There is a difference in driving means between the central screed and the widener screed.

  FIG. 1 shows the driving means of the tamper device 22 in the central screed 11. A plurality of V belts 45 are wound between the pulley 42 fixed to the journal portion 33 a and the pulley 44 solidified on the motor shaft 43 a of the motor 43.

  The motor 43 is fixed to a slide base 46 provided on the frame 23A so that its position can be adjusted in the front-rear direction of the arrow shown in the figure.

    Here, since the V-belt 45 is wound in the front-rear direction, the distance between the shafts of the belt device hardly changes even when the vertical position of the journal portion 33a is adjusted. Therefore, the change in driving force due to the vertical position of the journal portion 33a is ignored. It is in the range that can be done.

    FIG. 3 shows the driving means of the tamper device 22 in the widener screed 15. The output shaft of the hydraulic rotary motor 48 fixed to the front plate 23e of the frame 23A and the shaft end portion provided continuously to the distal end side of the journal portion 33a of the eccentric shaft 33 are connected by a universal joint 49. The universal joint 49 and the output shaft of the hydraulic motor 48 or the shaft end portion of the eccentric shaft 33 are both connected via a spline or key so as to transmit the rotational force, and either end portion of the universal joint 49 is axially moved. It is possible to move.

    When adjusting the vertical position of the tamper edge 25, the eccentric shaft 33 moves up and down with respect to the base plate 23, and the shaft center of the hydraulic motor 48 and the journal portion 33a of the eccentric shaft 33 are different, so that a universal joint 49 is used. is there.

    In the above description, the eccentric amount of the eccentric shaft 33 is 1.5 millimeters, and the rotational speed of the eccentric shaft 33 is 800 r. p. m.

(Pressure device for tamper edge)
The tamper edge pressurizing device 24 always pulls the strike-off 21 and the base plate 23 regardless of their relative positions, pressurizes the tamper-edge contact surface 21f of the strike-off 21 and the front contact surface 25d of the tamper-edge 25 and An elastic member such as a spring member 52 is provided as a pressing member that pressurizes the rear contact surface 25 c and the tamper edge contact surface 23 d of the base plate 23. Details will be described below.

    As shown in FIGS. 1 and 2, one end is pivotally attached to the lower part of the back of the strike-off 21 with a pin 51 and extends backward in the traveling direction of the asphalt finisher, and the other end is inserted through a bracket 23j provided on the frame 23A. A tension bar 24a having a male screw is provided. The tension bar 24a passes over the tamper bar 26. Alternatively, in the illustrated case, the tamper bar 26 is inserted through a notch (not shown) on the upper edge.

    A yoke portion 24a1 at one end of the tension bar 24a sandwiches a bracket 21g fixed to the back portion of the strike-off 21 by welding, and a pin 51 is just fitted in each hole of the yoke portion 24a1 and the bracket 21g.

    The portion of the bracket 23j at the rear of the frame 23A through which the tension bar 24a is inserted is a U-groove 23j1, and the tension bar 24a can rotate upward about the pin 51.

    An elastic member is inserted on the other end side of the tension bar 24a. In this example, the spring member 52 is used as the elastic member. Specifically, a compression coil spring wound with a wire having a square cross section is used. The spring member 52 uses the bracket 23j as a spring seat, and is tightened by a nut 54 which is a screw member screwed through a washer 53 inserted into the tension bar 24a. Due to compression of the spring member 52 between the bracket 23j and the washer 53, the strike-off 21 and the base plate 23 are pressed through the tamper edge 25 with the tension bar 24a.

    In this example, the spring member 52 is a compression coil spring having an outer diameter of 30 millimeters or 35 millimeters. The tension bar 24a has a diameter of 12 millimeters, and the male thread at the other end is a JIS standard thread (normal thread). The tightening torque of the nut 54 is 80 kg-m, and when the outer diameter of the spring member 52 is 30 mm, a tension force of about 300 kg is generated on the tension bar 52. Similarly, when the outer diameter is 35 mm, a tensile force of about 400 kg is generated.

    The tension bar 24a, the strike-off bracket 21g, the bracket 23j of the frame 23A, etc. are on both sides in the width direction (longitudinal direction) of each of the screeds 11 and 15, and there are two places.

(Function)
Next, the operation of the above configuration will be described. When the asphalt finisher advances in the direction of the arrow A in FIGS. 6 and 7, the central screed 11 and the widener screed 15 advance in the direction of the arrow A as shown in FIGS. The composite material sent from the hopper 17 by the conveyor 18 in the direction of the arrow shown in FIGS. 6 and 7 is sent to the left and right sides by the screw blades 19 arranged in the direction perpendicular to the traveling direction of the asfast finisher. Scattered on top.
The spread mixture is pushed by the central screed 11 and the widener screed 15 as the asphalt finisher advances, and is crushed, vibrated and pressurized by these lower surfaces.

    The above operation will be described in detail. The lower surfaces of the screeds 11 and 15 have an attack angle as a whole. The composite material pushed forward by the strike-off 21 is in a state where it is received on the lower surface thereof, and the strike-off 21 is made into a thin layer and compressed with a light force. Subsequently, as the asphalt finisher advances, the composite material through which the strike-off 21 has passed is crushed by the tamper edge 25.

    In the central screed 11, the motor 43 is rotating, the pulley 42 is rotated from the pulley 44 via the V belt 45, and the eccentric shaft 33 rotates. In the widener screed 15, the hydraulic motor 48 rotates and the eccentric shaft 33 rotates through the universal joint 49.

    In any of the screeds 11 and 15, the pin portion 33 b is swung by the rotation of the eccentric shaft 33, and the upper portion of the eccentric ring member 31 follows the pin portion 33 b and the swirling lower portion mainly moves up and down. Next, the behavior of the tamper device 22 will be described in detail.

(Tamper device behavior)
FIG. 8 is a view for explaining the rotation of the eccentric shaft 33, the displacement of the tamper edge 25, the displacement of the strike-off 21, and the action of the base plate 23.

Since the journal portion 33a of the eccentric shaft 33 is rotatably supported by a bearing bracket 34 fixed to the frame 23A, the relative position between the shaft center C1 of the journal portion 33a and the tamper contact surface 23d of the frame 23A is fixed. is there.
Now, it is assumed that a perpendicular line passing through the center C2 of the pin portion 33b and the center C1 of the journal 33a at the top dead center passes through the bisected position between the front contact surface 25d and the rear contact surface 25c of the tamper edge 25. This perpendicular will be referred to as a continuous center line RL. The tamper edge contact surface 23d of the base plate 23 is a vertical surface. The state in which the base plate 23 and the tamper edge 25 are in surface contact is when the pin portion 33b is at the top dead center or the bottom dead center with respect to the eccentric rotation of the eccentric shaft 33 (see FIGS. 8A and 8D). In FIG. 8, the amount of eccentricity of the eccentric shaft 33 is exaggerated and drawn to make it easier to understand the operation.

    FIG. 8A shows a state where the pin portion 33b is at the top dead center. At this time, the rear contact surface 25c of the tamper edge and the tamper edge contact surface 23d with respect to the base plate 23 are in surface contact. At this time, the tamper edge front contact surface 25d and the strike-off counter tamper edge contact surface 21f are in surface contact. At this time, the front contact surface 25d and the rear contact surface 25c of the tamper edge are parallel in this example, and the lower surface (grounding surface) 25b is a horizontal surface.

  8A, when the eccentric shaft 33 rotates in the direction indicated by the arrow C, the pin portion 33b rotates from the top dead center in the direction indicated by the arrow C and immediately depresses the tamper edge 25, and the continuous center line RL moves upward at the right side. Since it is displaced and tilted, the lower left corner 25e of the tamper edge 25 comes into linear contact with the tamper edge contact surface 23d of the base plate 23. Further, the upper right corner 25f of the tamper edge 25 linearly contacts the strike-off counter tamper edge contact surface 21f. At the same time, the strike-off 21 is pushed by the corner 25f of the tamper edge, and the arrow against the spring force of the spring member 52 of FIGS. 1 and 2 is centered on the pin 36 pivoting the strike-off 21 on the frame 23A. Rotate in the direction of d. At this time, the strike-off 21 compresses the spring member 52, which is an elastic member, via the pin 51, the tension bar 24a, the nut 54, and the washer 53. The tamper edge corner 25e slides downward on the tamper edge contact surface 23d of the base plate 23. Further, the tamper edge corner 25f slides downward on the strike-off counter tamper contact surface 21f.

  As shown in FIGS. 8B to 8C, when the pin portion 33b rotates in the direction of arrow C and the angle of rotation from the position shown in FIG. The center line RL has a substantially maximum inclination with respect to the vertical line. At this time, the angle α formed between the rear contact surface 25c of the tamper edge and the tamper edge contact surface 23d of the base plate 23 is substantially maximum with the corner 25e as a vertex. The strike-off 21 further rotates around the pin 36 in the direction of the arrow 2 to reach the rotation limit position. At this time, the angle β formed between the front contact surface 25d of the tamper edge and the tamper edge contact surface 21f of the strike-off 21 is substantially maximum with the angle 25f as a vertex. At this time, the tamper edge corner 25e continues to slide downward relative to the tamper edge contact surface 23d of the base plate 23, and the tamper edge corner 25f slides downward relative to the strike-off counter tamper edge contact surface 21f.

  From FIG. 8C, when the pin portion 33b rotates in the direction of the arrow C, the angle of the continuous center line RL with respect to the vertical line decreases and the going angles α and β also decrease. In FIG. 8D, the contact angles α and β are both zero. At this time, the tamper edge 25 is in the lowest position, the front contact surface 25d is in surface contact with the strike-off counter tamper edge contact surface 21f, and the rear contact surface 25c is in surface contact with the tamper edge contact surface 23d of the base plate.

  The lowering of the tamper edge 25 in FIGS. 8 (a) to 8 (d) causes the composite material to be compacted. Next, as shown in FIGS. 8D to 8E, when the pin portion 33b rotates in the direction of the arrow C, the link center line RL moves to the left because the pin portion 33b moves to the left. The tamper edge angle 25h is in line contact with the tamper edge contact surface 23d of the base plate 23, the angle 25g is in line contact with the strike off counter tamper edge contact surface 21f, and the angles 25f and 25g are raised. The lower surface 25b of the tamper edge 25 is separated from the compacted material surface.

  8 (d) to 8 (a), the pin portion 33b rotates in the direction indicated by the arrow C, whereby the tamper edge corner 25h slides against the tamper edge contact surface 23d of the base plate 23, and the corner 25g corresponds to the strike-off 21 pair. Sliding with the tamper edge contact surface 21f, the tamper edge 25 rises.

  8A, the tamper edge front contact surface 25d is in surface contact with the tamper edge contact surface 21f of the strike-off 21, and the rear contact surface 25c is in contact with the tamper edge contact surface 23d of the base plate 23. Contact.

  The mixed material is squeezed by the lowering of the tamper edge 25 in FIGS. 8 (a) to 8 (d). The composite material by this is compacted to the lower layer side.

    When the tamper edge 25 moves up and down as described above, the tamper edge 25 slides relative to the base plate 23 and the strike-off 21. At this time, the amount of change in the distance between the tamper edge contact surface 23d of the base plate 23 and the strike-off counter tamper edge contact surface 21f is very small. If the distance from the journal portion 33a center C1 of the eccentric shaft 33 to the tamper edge 25 (to the center C1 of the journal portion 33a and the lower surface 25b of the tamper edge) is compared to, for example, 300 millimeters, the eccentric amount of the eccentric shaft 33 is As small as 1.5 mm. Accordingly, the maximum values of αmax and βmax are about 1.5 / 600 rad, and the gaps between the tamper edge corners 25e and 25f and the tamper edge contact surfaces 23d and 21f of the strike plate 21 at the corners 25e and 25f, respectively. The sizes of g1 and g2 are about 0.05 millimeters when the height of the tamper edge 25 is h = 20 millimeters.

  As described above, since the tension bar 24a is located closer to the pin 36 supporting the frame 23A with the base plate 23 of the strike-off 21 than the tamper edge 25 in the vertical direction, the axial displacement of the tension bar 24a is about 0.05 mm or less. It is. While the tamper edge 25 moves up and down, the spring force of the spring member 52 is substantially constant, and the tamper edge 25 is held between the base plate 23 and the strike-off 21 with substantially constant spring force. Accordingly, a substantially constant frictional force always acts between the tamper edge front contact surface 25d and the strike-off counter tamper edge contact surface 21f and the tamper edge rear contact surface 25c and the tamper edge contact surface 23d of the base plate 23.

  According to the asphalt finisher having the above-described configuration, the tamper edge and the base plate and the tamper edge and the strike-off are always in contact with each other and the contact surface is pressurized by the spring force, so that no gap is generated between the contact surfaces. Accordingly, it is possible to prevent asphalt from entering from the tamper edge and the base plate and between the tamper edge and the strike-off. Since the sliding between the tamper edge and the base plate and between the tamper edge and the strike-off, the asphalt having a low viscosity is like a lubricant and also acts as a material seal. This makes it difficult to deposit asphalt on the base plate near the tamper edge and on the strike-off.

  The contact surface before and after the tamper edge, the base plate and the strike-off contact surface of each tamper-edge wear, but the contact surface between the tamper-edge and the base plate and between the tamper-edge and the strike-off is added by the tamper edge sandwiched between the base plate and the strike-off. The contact state is always maintained because it is pressed.

  As the eccentric shaft rotates, the tamper edge moves up and down and tilts, but the tamper edge front contact surface, strike-off counter tamper edge contact surface, tamper edge rear contact surface, and base plate counter tamper edge contact surface are under almost constant pressure. As the asphalt finisher with the tamper device according to the embodiment has no significant vibration (comparatively proved), the asphalt finisher of the example has no vibration even if it gives the strike-off.

    In addition, when the composite material is crushed by the tamper edge, the composite material guided by the strike-off is hardly pressurized (the composite material is soft), and the vibration of the asphalt finisher is significant depending on the action of the tamper edge to pulverize the composite material. It does not increase. The tamper edge is sandwiched and pressed between the base plate and the strike-off by a spring force smaller than the fastening force pulling the base plate and the strike-off through the tamper edge, and the tamper device and the tamper device It is clear that the vibration of the asphalt finisher is not significantly increased by the vibration of the tamper device itself because the inertia weight of the moving part of the drive device which is the drive means is small.

(Behavior of conventional tamper device)
Here, let us consider what kind of phenomenon occurs in the conventional example.

  In the conventional example, the relational position between the base plate and the strike-off is adjustable, but is fixed after the adjustment. This fixing is supposed to be immovable with the base plate and the strike-off tightened as tightly as possible.

    For example, in the state of FIG. 9 (a) or (c), the tamper edge is firmly tightened by strike-off with the base plate.

  Therefore, for example, as shown in FIG. 9B, when the base plate 23 and the strike-off 21 are drawn when the continuous center line RL is substantially at the maximum angle with respect to the vertical, the tamper edge angles 25e and 25f become the base plate 23 and the strike-off 21, respectively. Pressed. When the force pulling the base plate 23 and the strike-off 21 increases, the tamper edge 25 tilts counterclockwise, reducing the angles α and β, and rotating the eccentric shaft 33 in the direction of arrow e. 9A, the tamper edge front contact surface 25d is a strike-off counter tamper edge contact surface 21f, and the tamper edge rear contact surface 25c is a tamper edge contact surface 23d of the base plate 23. As shown in FIG. And contact each other. As described above, the base plate and the strike-off are conventionally tightened as tightly as possible, so that the base plate 23 and the strike-off 21 are strongly pulled and tightened even after the contact surfaces 25d and 21f and 25c and 23d are in surface contact.

  Incidentally, FIG. 9B is as described above because the pin portion 33b faces horizontally, but in FIG. 9B, the continuous center line RL is the center of the pin portion 33b of the eccentric shaft 33. Suppose that the center of the pin portion 33b is at a position in contact with the circle K drawn. At this time, when the base plate 23 and the strike-off 21 are drawn together, the pin portion 33b may rotate in the direction indicated by the arrow H or in the direction indicated by the arrow C. When it is rotated in the direction of arrow C, as shown in FIG. 9C, the tamper edge 25 is lowered while decreasing the angles α and β, and the strike-off 21 with respect to the tamper edge 25 and the contact of the base plate 23 are surface contact. It becomes.

If the base plate and the strike-off are pulled in a state where the continuous center line RL is inclined or not inclined as described above, a state as shown in FIG. 9A or 9C is obtained.
When the motor 43 and the hydraulic motor 48 are driven, in FIG. 9A, when the pin portion 33b of the eccentric shaft 33 rotates in the direction of the arrow C, the tamper edge 25 tilts and descends according to the tilt of the continuous center line RL. To do. At that time, the tamper edge corners 25f and 25e are expanded between the strike-off 21 and the tamper edge contact surfaces 21f and 23d of the base plate 23. A large force is rapidly generated between the tamper edge corner 25f and the strike-off counter tamper edge contact surface 21f, and between the tamper edge corner 25e and the tamper edge contact surface 23d of the base plate 23. And this force becomes the maximum when the pin part 33b rotates to FIG.9 (b). At this time, the change in the force applied by the tamper edge 25 to the strike-off 21 and the base plate 23 is large. Since the base plate 23 and the strike-off 21 are fastened so as to approach each other in the state of FIG. 9A, the strike-off 21 cannot escape from the base plate 23, so that the tamper edge corners 25e, 25f Therefore, since the tamper edge 25 moves in a state where the base plate 23 and the strike-off contact surfaces 23d and 21f of the strike-off are pressed, a large sliding resistance is generated.

  As shown in FIGS. 9A to 9C, the rotation of the pin portion 33b causes the corners 25e and 25f of the tamper edge 25 to slide on the base plate 23 and strike-off counter tamper edge contact surfaces 23d and 21f to be lowered. In the state c), the tamper edge front contact surface 25d and the strike-off counter tamper edge contact surface 21f are in surface contact, and the tamper edge rear contact surface 25c is in surface contact with the tamper edge contact surface 23d of the base plate 23.

  At this time, the contact force between the tamper edge corners 25e and 25f and the tamper edge contact surfaces 23d and 21f of the base plate 23 and the strike-off 21 decreases rapidly.

    Similarly, as shown in FIGS. 9C to 9D and FIGS. 9D to 9A, the same phenomenon occurs in each half rotation of the pin portion 33d in the direction of arrow c.

    For this reason, it is considered that the vibration of the asphalt finisher with the tamper device is larger than that of the asphalt finisher without the tamper device due to the behavior of the tamper edge 25.

    Under the large contact pressure between the tamper edge and the base plate and between the tamper edge and the strike-off, the corner of the tamper edge slides on the contact surface against the tamper-edge, so that the contact surface of the tamper-edge of the base plate and the strike-off is dominant compared to the wear of the tamper edge. It will be worn significantly (see FIG. 10). This is because, while the tamper edge is quenched from high-strength steel or the like, the material of the base plate and the portion constituting the strike-off contact surface of the striker edge is medium-hard steel (for example, SC45). . Note that even if the components of the tamper edge, base plate, and strike-off counter-tamper edge contact surface are the same, the wear on the anti-tamper edge contact surface is only reduced.

(Wear state of contact surface between tamper edge and tamper edge)
FIG. 10 shows a case where the base plate 23 and the strike-off 21 are fastened in surface contact with the tamper edge 25 so that the relational position between the base plate 23 and the strike-off 21 is constant at the positions shown in FIGS. 2 shows a state in which the tamper edge 25 having a square cross section wears the tamper edge contact surface 23d of the base plate 23 and the strike-off 21.

  In FIG. 10, when the pin portion 33 b rotates 180 degrees in the direction of arrow C from the state shown in FIG. 9A, the tamper edge 25 tilts to the right. The tamper edge contact surface 23d of the base plate is worn like a concave surface 23d1 in the figure by a tamper edge angle 25e between L1. At the same time, the portion between S1 of the strike-off counter tamper edge contact surface 21f is worn by the tamper edge angle 25f as in the illustrated concave surface 21f1.

  In FIG. 10, when the pin portion 33 b further rotates 180 degrees in the direction of arrow C from the state shown in FIG. 9C, the tamper edge 25 tilts leftward. The tamper edge contact surface 23d of the base plate 23 is worn like a concave surface 23d2 in the figure by a tamper edge angle 25h between L2. At the same time, the portion between S2 of the strike-off counter tamper edge contact surface 21f is worn by the tamper edge angle 25g as shown in the illustrated concave surface 21f2.

  In the embodiment, at this time, the tamper edge is sandwiched between the base plate and the strike-off with a substantially constant force, so that the wear is small. In addition, the contact surface between the tamper edge and the base plate and the contact surface between the tamper edge and the strike-off are pressurized with a substantially constant pressure regardless of wear, so that no gap is generated between the tamper edge and the base plate and between the tamper-edge and the strike-off. Therefore, the asphalt in the mixed material spread on the roadbed side does not accumulate around the tamper device, on the frame near the base plate, on the strike-off, or in the tamper device drive device.

  In the conventional example, when the tamper edge is inclined, the space between the tamper edge, the base plate, and the strike-off is forcibly expanded, so that a large force is generated on each of the contact surfaces 21f, 25c, 25d, and 23d, resulting in fast wear. In the worn state as shown in FIG. 10, at least the gap g3 occurs at the intersection line between the concave surfaces 23d1 and 23d2, and the gap g4 occurs at the intersection line between the concave surfaces 21f1 and 21f2 as shown in the figure. The gaps g3 and g4 are always generated during the vertical movement of the tamper edge 25, and asphalt enters the screed through the gaps g4 and g3. In order to avoid this, it is necessary to frequently tighten the fastening between the base plate and the strike-off. Since the base plate and the strike-off are strongly tightened, the force generated at the contact surface between the tamper edge and the base plate and between the tamper edge and the strike-off changes suddenly, thereby increasing the vibration of the asphalt finisher. The base plate and the strike-off are frequently fastened to promote wear.

(Other Example 1)
In the above, the shape of the tamper edge is square, but the contact surface of the base plate and the strike-off to the tamper edge is a flat surface, and the front contact surface and the rear contact surface of the tamper edge are envelope surfaces with respect to this plane accompanying the vertical movement of the tamper edge (middle and high Surface).

  In this way, even if the front contact surface and the rear contact surface of the tamper edge are set to a medium-high surface, according to the conventional example, the base plate and the strike-off are firmly fastened, so the tamper edge and the base plate and the tamper edge and the strike-off are The wear of the contact surface between them is rapid and the gap between them can be made faster. Similarly, in order to suppress the occurrence of a gap due to contact wear, the base plate and the strike-off must be tightened frequently in order to keep them firmly. And since the base plate and the strike-off are firmly fastened, the vibration of the asphalt finisher remains unchanged.

  According to the present embodiment, even if the front contact surface and the rear contact surface of the tamper edge are medium and high surfaces, the contact pressure on the front contact surface of the tamper edge, the base plate applied to the rear contact surface, and the strike-off contact surface against the tamper edge is substantially constant. As a result, there is no gap between the tamper edge front contact surface and the strike-off counter tamper edge contact surface, and between the tamper edge rear contact surface and the base plate counter tamper edge contact surface, and asphalt does not enter the machine. . The contact surfaces 21f and 25d, 25c and 23d have a small contact pressure and less wear. Furthermore, there is no need to retighten the base plate and strike-off.

(Other Example 2)
As shown in FIG. 11, the tamper device drive device is the same as that described above, and when the tamper device uses a linkage 47 in which the pin portion 33b of the eccentric ring 33, the upper portion of the tamper edge 25 and the pin 25i are connected. The tamper edge 25 keeps the surface contact state roughly when the strike-off edge 21 tilts around the pin 36 due to wear with the tamper-edge contact surface 23d of the base plate 23 and the strike-off counter-tamper edge contact surface 21f. The tamper edge contact surfaces 23d and 21f of the strike-off 21 are worn and a gap is formed between the tamper edge 25, the base plate 23 and the strike-off 21. Even if this gap occurs, the relative position of the base plate 23 and the strike-off 21 does not change in the conventional example, so the asphalt on the roadbed side enters the tamper edge 25 through this gap. Therefore, even in this case, it is necessary to frequently adjust the relational position between the base plate and the strike-off. In the present embodiment, the effect as described above is also produced in the tamper device using the continuous 47.

  In the embodiment, the compression coil spring 52 is used. However, as the elastic member, other types of spring members such as leaf springs can be used as long as the response to expansion and contraction is fast. Further, a pneumatic cylinder may be used in place of the compression coil spring 52.

( Example of the present invention )
The asphalt finisher provided with the tamper device has a vibration device that vibrates the base plate of the screed, and the tamper device generates vibration. Therefore, the asphalt finisher vibrates more greatly than an asphalt finisher without the tamper device. However, even in the latter case, the screed is vibrated greatly because it is provided with a vibrating device. In particular, the step on which the screed man rides vibrates greatly because it must be attached in the form of a cantilever to the frame on which the vibration device is attached. In particular, the step attached to the widener screed vibrates greatly due to the positional relationship. Moreover, the steps attached to the widener screed are boarded with the screedman standing almost always. So, as I already mentioned, it often hurts my knees.

  An object of the present invention is to provide an asphalt finisher equipped with a vibration damping device that is effective for an asphalt finisher with a tamper device, but is also effective for preventing vibration of a step even for an asphalt finisher without a tamper device.

  In this embodiment, a step is provided on a support member of a frame via a shock absorber. Details will be described below.

  As shown in FIGS. 6 and 7, steps 10 and 20 are provided at the rear end of the asphalt finisher for the screed man to stand and ride as viewed from the traveling direction. Step 10 is provided in the central screed 11. Step 20 is provided in the widener screed 12.

  This embodiment is applied to step 20, but may be applied to step 10.

Step 20 is provided so as to be supported by the frame 23A (see FIG. 12) of the widener screed 12.

  FIG. 12 is a perspective view of the widener screed 12 as seen from the left rear. A bracket 23m projects from the frame 23A in the direction opposite to the traveling direction of the asphalt finisher. The bracket 23m uses channel steel, and the base is welded to the frame 23A. A bracket 23m belonging to the frame 23A serves as a support member for the step 20.

  The step 20 is supported via a spring device 55 and a rubber damper 56 provided on the bracket 23m. Step 20 is an elongated rectangular planar figure. The brackets 23m are provided at two positions so as to support the short side of the step 20, and are parallel to each other.

  The step 20 is supported on the bracket 23m via a shock absorber described below.

  On each bracket 23m, a spring device 55 and a rubber damper 56 are provided close to each other, and two sets are provided. Therefore, step 20 is supported at both ends in the longitudinal direction.

Step 20 is made in the shape of a hollow box. As shown in FIG. 13, in step 20, a lower plate 20b is provided in parallel with the sliding plate 20a on which the screed man rides, and the entire periphery of the sliding plate 20a and the lower plate 20b is an integrated body which is a side plate.

  The step 20 is made of a steel plate having a thickness of 4.5 mm, and the upper side cover plate 20a and the side plate are made of a strip steel plate.

  FIG. 13 is a longitudinal sectional view including the spring device 55 and the rubber damper 56.

  The spring device 55 has a spring 58 that is fitted between a circular hole 23m1 provided in the bracket 23m and is fitted between the bottom 57b of the cylindrical container 57 supported by the bracket 23m with a collar 57a and the cover plate 20a. The spring 58 is inserted through the hole 20b1 of the lower plate 20b. The spring 58 is a compression coil spring having a cross section wound with a wire having a thickness of 2.5 mm and a width of 4 mm. The outer diameter of the spring 58 is 25 mm, the number of turns is 15, and the total length of 90 mm is compressed to 80 mm and attached.

  A compression means is provided to keep the spring 58 pre-compressed. This compression means has one end fixed to the cover plate 20 a, a planting bolt 59 that passes through the bottom 57 b of the container 57 through the center of the spring 58, and a nut 62 that is screwed into the planting bolt 59 via a washer 61.

  The rubber damper 56 having both ends fixed to the lower plate 20b and the bracket 23m is a fitting having a screw member 56c integrally formed with the circular plate 56b at both ends of a cylindrical vibration-proof rubber 56a made of strong damping vibration-proof rubber. I have. The fixture is made of iron. The disc 56b and the vibration isolating rubber 56a are integrated by vulcanization adhesion. One male screw member 56c is screwed into the bracket 23m. The other screw member 56c protrudes into the step 20 through the lower plate 20b. A nut 63 is screwed into the other screw member 56c. That is, the rubber damper 56 connects the bracket 23 m and the step 20.

    In the above state, when the weight of one screedman 60 kg, which is assumed to be the load of step 20, is applied to the four springs 58, it is bent just 10 millimeters. This deflection of 10 millimeters tightens the nut 62 to deflect the spring 58 by 10 millimeters. The rubber damper 56 is in a state where it is neither compressed nor pulled in the above state. Speaking of only one spring 58, when 15 kg, which is a quarter of the weight of step 20 and a quarter of the body weight, is added, the spring 58 is bent by 10 mm. At this time, neither the compressive force nor the tensile force is applied to the rubber damper 56.

    Here, since the rubber damper 56 only needs to generate a damping force when the step 20 is displaced both upward and downward in the vibration process, the rubber damper 56 applies the following load corresponding to the weight of the step 20 and the weight of the screed man. 56 may be added in advance. This load may compress the damper rubber 56a in the vertical direction, or may pull it.

  The rubber damper 56 has a vibration-proof rubber 56a having a diameter of 32 millimeters and a height of 22 millimeters. The damping rubber 56a is a strong damping damping rubber.

  A vibration device (not shown) provided on the frame 23A is driven. Alternatively, the tamper device 22 is driven at the same time. Then, although the purpose of the vibration device is to vibrate only the base plate 23, the frame 23A is vibrated. Further, since the tamper device 22 is supported by the frame 23A, the vibration based on the drive of the tamper device 22 is transmitted to the frame 23A. These vibrations are transmitted to the bracket 23m. When the screed man is on the step 20, the spring 58 is bent so that the spring force of the spring 58 is balanced with the weight of the screed man plus the weight of the step 20, so that the vibration isolating rubber 56 is compressed. Neither is it pulled. Accordingly, the vertical movement component of the vibration of the bracket 23m is attenuated by the vibration isolating rubber 56a both when the bracket 23m is displaced upward by vibration and when it is displaced downward by vibration. The rubber damper 56 also attenuates vibration (lateral vibration) in the horizontal plane of the bracket 23m.

  As described above, according to this embodiment, step vibration is suppressed. This greatly eliminates the negative effects on the screed man. This adverse effect is less sensation of sensation due to vibration. In the long term, the burden on the knees of the screed man will be reduced, and it will no longer be possible to stay long as a workplace by hurting the knees.

  By supporting the step with the frame via the shock absorber of the present invention, vibration transmitted from the frame side to the step is reduced, contributing to improvement of the working environment.

It is a longitudinal cross-sectional view of a center screed. It is a longitudinal cross-sectional view of a wide nurse screed. It is a front view which sees the inside of a wide nurse screed. It is a schematic perspective view of a pressurizing device. It is a schematic perspective view of a tamper device. It is a side view of an asphalt finisher. FIG. 7 is a plan view of FIG. 6. (A)-(e) is a side view which shows the effect | action of the tamper apparatus of an Example. (A)-(b) is a side view which shows the effect | action of the tamper apparatus of a prior art example. It is a side view which shows the abrasion state around a tamper edge. It is a schematic diagram which shows another tamper device. It is a perspective view for showing a buffer device of a step. It is a longitudinal cross-sectional view of the buffer device of a step.

Explanation of symbols

C1 ... journal center C2 ... center RL ... continuous center line g1, g2, g3, g4 ... gap 1 ... chassis frame 2 ... wheel 3 ... pin 4 ... arm 5 ... screed device 7 ... fixed shaft 8 ... central screed frame 9 ... Operation handle 10 ... Step (center)
11 ... Center screed 12 ... Widener screed 13 ... Widener frame 14 ... Guide bar 15 ... Widener screed 17 ... Hopper 18 ... Conveyor 19 ... Screw blade 20 ... Step (Widener) 20a ... Fin plate 20b ... Lower plate 20b1 ... Hole 21 ... Strike-off 21a ... Introduction part 21b ... Picking plate part 21c ... Front plate part 21
d ... Circular arc 21e ... Bracket 21f ... Tamper edge contact surface 21f1, 21f2
... Concave surface 21g ... Bracket 22 ... Tamper device 23 ... Base plate 23A ... Frame 23a ... Lower surface (grounding surface) 23b ... Combustion chamber 23c ... Top plate 23d ... Tamper edge contact surface 23d1, 23d2 ... Concave surface 23e ...
Front plate 23f ... Upper plate 23g ... Side plate 23h, 23i, 23j ... Bracket 23k ... Flange 23m ... Bracket 23m1 ... Round hole 24 ... Pressure device 24a ... Tension bar 24a1 ... Yoke part
25 ... Tamper edge 25a ... Slope 25b ... Lower surface (grounding surface) 25c ... Rear contact surface 2
5d ... front contact surface 25e, 25f, 25g, 25h ... corner
26 ... Tamper bar 27 ... Bolt 28 ... Connecting member 28a ... Angle member 28b ... Bar material 29 ... Bolt 30 ... Bolt 31 ... Eccentric ring member 32 ... Bearing 33 ... Eccentric shaft 33b ... Pin part
34 ... Bearing bracket 34a ... Bracket body 34a1 ... Elongated hole 34e ... Bolt 35a ... Through screw 35c, 35d ... Nut 36 ... Pin 37 ... Support member 37a ... Bracket 37b ... Horizontal piece 37c ... Hard piece 37d ... Elongate hole 38 ... Support member 38a ... Bracket 38b ... Slot
DESCRIPTION OF SYMBOLS 39 ... Adjustment screw 40, 41 ... Bolt 42 ... Pulley 43 ... Motor 43a ... Motor shaft 44 ... Pulley 45 ... V belt 46 ... Slide base 47 ... Linkage 48 ... Hydraulic rotary motor 49 ... Universal joint 51 ... Pin 52 ... Spring member (Elastic member)
53 ... Washer 54 ... Nut 55 ... Spring device 56 ... Rubber damper 56a ... Anti-vibration rubber 56b ... Disc 56c ... Male screw member 57 ... Container 57a ... Collar 57b ... Bottom 58 ... Spring 59 ... Planting bolt 61 ... Washer 62 ... Nut 63 ... Nut

Claims (2)

In the asphalt finisher that performs asphalt pavement construction,
A traveling device for traveling an asphalt finisher;
A composite material transporting device for transporting the composite material from the hopper at the front of the vehicle to the rear of the vehicle;
Screw blades that spread the composite material to the width of asphalt pavement,
A screed equipped with a vibration device and vibrated and pressed against the surface on which the composite material is to be constructed,
A step for boarding a screed man provided at the rear end of the screed;
Have
The step is provided via a shock absorber on a support member of a frame having a base plate that vibrates and presses the composite material provided on the screed, and the shock absorber includes a rubber damper, a spring and a spring compression means, The spring is compressed in advance by the compression means by the weight of the step and the length of the screedman by the weight of the screedman. When the spring is pre-compressed, the damping force of the rubber damper acts in the vibration process upward of the step. The asphalt finisher is characterized in that the rubber damper has no compression deflection or a small compression deflection. The asphalt finisher according to claim 1 , further comprising a tamper device.

Images