A mechanical linkage having a geometry designed to substantially hold the plane of a main screed and the plane of an extension screed at a generally constant relative angle with respect to one another through a predetermined range of screed depth adjustments. The linkage is configured to allow the extension screed to be raised and lowered by an amount sufficient to compensate for angle of attack and elevation changes in the main screed. In particular, the linkage compensates for the effect of the radial distance differences from the axis of rotation of tow bars of the main screed and extension screed as the main screed pivots with respect to the tow point of the tow bars for different asphalt mat depths. An alternate embodiment includes actuators, together with sensors, for sensing the position of the extension screed with respect to the main screed and automatically compensating for changes in main screed position to properly orient the extension screed with respect to the main screed.

Adjustable screed system

The invention provides a screed height-difference adjusting device, a paver and a screed high-difference adjusting method. The screed height-difference adjusting device is used for adjusting the height difference between an auxiliary screed and a main screed of the screed, and comprises an angle sensor, an adjusting oil cylinder and a controller, wherein the angle sensor is used for measuring working elevation angle of the main screed; the adjusting oil cylinder is used for driving the auxiliary screed to displace in the height direction; and the controller is used for receiving the working elevation angle measured by the angle sensor, calculating the target displacement of the auxiliary screed in the height direction according to the working elevation angle, and controlling the height difference between the auxiliary screed and the main screed by controlling the adjusting oil cylinder. By virtue of the technical scheme, the angle sensor reads out the working elevation angle of the main screed and the auxiliary screed, and the adjusting oil cylinder determines the to-be-adjusted height value according to the working elevation angle to automatically flex and adjust the height difference. Therefore, the manual work is avoided; and time and force are saved. Meanwhile, the precision of the adjusting value calculated according to the working elevation angle is higher; the evenness of the paved road surface is ensured; and the paving quality of the road is improved.

Screed height-difference adjusting device, paver and screed high-difference adjusting method

Screed device for spreading machine and spreading machine applying same

PROBLEM TO BE SOLVED: To provide an easily constructible longitudinal groove forming technique.SOLUTION: A longitudinal groove forming tool is installed on a bottom surface of a screed baseplate. The longitudinal groove forming tool is comprised of a plurality of beam members 12. The beam members 12 are disposed in parallel and series (beam member 12A and 12B) with the screed direction of travel as the axial direction. While leveling a pavement surface, the beam members 12 apply a pressing force to a leveled surface and form a longitudinal groove when moved in the leveling direction of travel while the pressing force is applied. The beam member 12B particularly can be detached easily.SELECTED DRAWING: Figure 14

Longitudinal groove forming tool for paving, paving method, and evaluation method for asphalt paving construction

The invention discloses a self-adjusting wire-hanging device suitable for hard soil construction The device include a screw-in type wire-hanging pile, an installation device, wires and a microcomputer, wherein the installation device is used for installing screw-in type wire-hanging piles, and the wires has the data transmission function The screw-in type wire-hanging piles are sequentially inserted into a roadbed at intervals in the direction of the road edge, the wires are connected between the adjacent screw-in type wire-hanging piles, the microcomputer is electrically connected with thescrew-in type wire-hanging pile located at the starting end of the roadbed through the corresponding wire and outputs marking data, the screw-in type wire-hanging piles can filter and intercept the marking data, each screw-in type wire-hanging pile includes a housing, a positioning base arranged in the housing and a rolling bearing arranged between the housing and the positioning base, the outer side wall of each housing is provided with a screw used for screwing in soil and several drive bosses cooperated with the installation device, and the several drive bosses are uniformly distributed inthe circumferential direction of the housings An inner ring of each rolling bearing is fixed in the axial direction, the positioning bases are sleeved with the inner rings of the rolling bearings, and the outer sides of outer rings of the rolling bearings fit and are fixedly connected with the inner sides of the housings

Self-adjusting wire-hanging device suitable for hard soil construction

PROBLEM TO BE SOLVED: To provide a screed device for a road paving machine capable of simply changing the position of an extension screed to that of an expansion screed and ensuring fixation at respective positions. SOLUTION: A pair of right and left expansion screeds for substantially expanding a uniformly placement area are arranged backward in the moving direction of a main screed 2 for uniformly placing an asphalt mixture to pave a road surface. Extension screeds 4, 4 in a foldable manner are provided in parallel backward of the main screed 2 outside both ends of the pair of right and left expansion screeds 3. A first cylinder 8 is secured to each of pairs of the expansion screeds 3 and the extension screeds 4 adjacent thereto to switch the position of the extension screed 4 into one of a parallel arrangement position where it is arranged in parallel to expansion screed 3 in the extension direction and a fold position where it is superposed backward in parallel onto the expansion screed 3 with the expansion thereof.

Screed device for road paving machine

PROBLEM TO BE SOLVED: To steplessly change a paving width up to above twice as much as a main screed in a screed device attached to a road paving vehicle such as an asphalt finisher. SOLUTION: A first telescopic screed 24 and a second telescopic screed 25 about the same in width as a main screed 23 are provided side by side in the rear in the advancing direction of the main screed 23, and support arms 26, 26 and 21, 27 are protrusively provided backward on both the upper outsides of the main screed 23 to support the first and the second telescopic screed 24, 25 so as to be laterally movable on each road surface. The first and the second cylinder 28, 29 are set mutually opposite in the upper part of the main screed 23, and each of their cylinder rods 28a, 29a is protruded through the holes of the support arms 26, 27 toward the outsides of the road surface width, and severally fixed to the upper left end face 30 of the first telescopic screed 24 and the upper right end face 31 of the second telescopic screed 25.

Screed device for road paving vehicle such as asphalt finisher

PROBLEM TO BE SOLVED: To provide a road paving machine capable of making an extended screed lie between an expansion screed and side plates within a short period of time and saving energy. SOLUTION: Side plates 5 arranging a pair of right and left backward in the forward direction of a main screed 2 paving a road surface by compacting an asphalt mixture and controlling the movement toward a shoulder side of the asphalt mixture at the outside of an expansion screed 3 substantially enlarging a range of compaction of the main screed 2 are moved forward to the shoulder side from the expansion screed side by means of a side plate moving device 11 to form an interval for making an extended screed 9 lie between the expansion screed 3 and side plates 5, and the extended screed 9 is provided to the inside of the interval. Then, the side plates 9 are fixed to the extended screed 9 with a fixed device 12.

Niwa Katsunori

Papers

Screed device for road paving machine

Screed device for road paving vehicle such as asphalt finisher

Road paving machine