Support structure for road paving machine and work steps used therein

Abstract

To make the area of a bottom plate as large as possible and to house a working step in a limited section.SOLUTION: A support structure of a working step comprises a bracket 6a attached to a left telescopic structure, a rotary bracket 8 attached to the bracket 6a rotatably in an upward direction, a left telescopic step base 7a attached to the rotary bracket 8, a bracket 6b attached to a right telescopic structure, a rotary bracket 8 attached to the bracket 6b rotatably in an upward direction, a right telescopic step base 7c attached on the rotary bracket 8, and a central step base 7c attached on the housing of a screed device so as to be rotatable upward. The connecting part between the rotary bracket 8 and the left telescopic step base 7a can be released. The connecting part between the rotary bracket 8 and the right telescopic step base 7c can be released.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a foldable support structure for steps of a road paver having an extendable screed. [Background technology]

[0002] Conventionally, as described in Patent Document 1, the working step (16) of a road paving machine (the symbol in parentheses is the symbol described in the patent document; the same applies below) is attached at a predetermined distance from the rear end face of the screed. As a result, the overall length of the paving machine increases by that amount. Therefore, for example, when loading a road paving machine onto a truck and transporting it, the space required to mount the road paving machine increases by the amount of the longer overall length of the road paving machine, which means that a larger truck must be used, resulting in an increase in the cost of transporting the paving machine.

[0003] In order to solve such problems, Patent Document 2 discloses a foldable structure for steps of a road paving machine having an extendable screed.

[0004] In Patent Document 2, a work center step (7) is attached to the rear end of an extendable screed (5) having extendable screed sections (10, 11) attached to a screed body (9). Furthermore, a vertical portion (24) of an L-shaped first bracket (22) is fixed to the screed body (9). A second bracket (23) is connected to a horizontal portion (25) of the first bracket (22) via a roller (32) and a roller shaft (31) that allow the second bracket (23) to move horizontally rearward and rotate up and down relative to the rear end surface of the screed body (9). The center step (7) is fixed to the second bracket (23). By drawing the second bracket (23) rearward and rotating it upward relative to the first bracket (22), the center step (7) can be folded into an upright position in which it abuts or is close to the rear end surface of the screed body (9).

[0005] The step described in Patent Document 2 can be folded up into an upright position in contact with or closely facing the rear end face of the screed body, thereby shortening the overall length of the road paving machine compared to conventional examples. Therefore, for example, when loading the road paving machine onto a truck for transport, only a small space is required for loading the road paving machine, allowing the use of a small truck and reducing the cost of transporting the paving machine. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-248576 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-287351 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the case of small road pavers such as those manufactured by the applicant, it is necessary to fit all functions within a limited size. In particular, the screeds for road pavers in the small special vehicle category must fit the equipment into a very small compartment.

[0008] The construction performance of the screed (construction flatness and tracking ability during operation) depends on the screed bottom plate shape and bottom plate surface pressure (kg / cm 2 However, in the case of small road paving machines, as mentioned above, the screed needs to be placed in a very small area, so the base plate pressure (kg / cm 2 ) tends to be higher. As a result, it is difficult to balance the above construction capabilities, and operators sometimes complain that operation is difficult.

[0009] Fig. 8(a) is a side view of a conventional screed device manufactured by the applicant of the present application. As shown in Fig. 8(a), the step rotates upward with respect to the rotation center as indicated by the arrow in Fig. 8(a), and is raised upward for use during work. In the screed device, a main bottom plate is disposed directly below the main frame, a left bottom plate is disposed directly below the left telescopic frame, and a right bottom plate is disposed directly below the right telescopic frame.

[0010] In the structure shown in Figure 8(a), when work is not being performed, the step must be folded downward around the center of rotation and stored. Therefore, the size of all the bottom plates, including the right bottom plate, must be kept small, taking into account the storage space for the step. As a result, the total area of ​​the bottom plates becomes small, which increases the surface pressure on the bottom plates.

[0011] With the step structure described in Patent Document 2, the step can be rotated upward, but because the bracket (22) is L-shaped, the horizontal part 25 protrudes rearward, and in the case of small road paving machines in particular, there is a possibility that it will not fit into the storage compartment.

[0012] In view of the above, an object of the present invention is to provide a road paving machine and a support structure for work steps used therein that can maximize the area of ​​the bottom plate and store the work steps in a limited compartment. [Means for solving the problem]

[0013] In order to solve the above problems, the present invention has the following features: The present invention is a support structure for a work step attached to a screed device of a road paving machine that can extend and retract the screed to the left and right, the support structure comprising a first bracket attached to the left telescopic structure of the screed, a first pivot bracket attached to the first bracket so as to be pivotable upward, and a support structure for a work step attached to the first pivot bracket. Can slide left and righta first telescopic step platform; a second bracket attached to the right telescopic structure of the screed; a second pivot bracket attached to the second bracket so as to be pivotable upward; and a step attached to the second pivot bracket. Can slide left and right It is characterized by having a second extendable step platform and a central step platform that is attached to the housing of the screed device so that it can rotate upward.

[0014] Preferably, when the screed device is retracted, the first and second telescopic step platforms can be stored inside the central step platform, and the first, second and central step platforms, as well as the first and second pivoting brackets, can be rotated upwards and folded for storage.

[0015] Preferably, the connection between the first pivot bracket and the first extendable step platform is releasable, and the connection between the second pivot bracket and the second extendable step platform is releasable.

[0016] Preferably, a bottom plate of the screed device is provided up to the lower rear ends of the first and second brackets.

[0017] The present invention also provides a road paving machine including a screed device having the above-described support structure for the working step. [Effects of the Invention]

[0018] According to the present invention, the first telescopic step platform, the second telescopic step platform, and the central step platform can be rotated upward via the first bracket and the first pivot bracket, and the second bracket and the second pivot bracket. This allows the lower parts of the support structures for these steps to be left open for the placement of a base plate. This allows the area of ​​the base plate to be maximized, and the work steps can be stored in a limited space.

[0019] By making it possible to disconnect each pivot bracket from each extendable step platform, interference with components within the screed device can be avoided, making it possible to make the step support structure more compact.

[0020] These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a side view of a road paving machine 1 when a step structure 5 according to an embodiment of the present invention is rotated downward (during operation). [Figure 2] FIG. 2 is a perspective view of the road paving machine 1 when the screed is extended, seen from diagonally above and behind. [Figure 3] FIG. 3 is a perspective view of the road paving machine 1 when the screed is extended, seen from diagonally below and behind. [Figure 4] 4 is a perspective view showing the structure of the work step from diagonally above and behind, in which the work step is shown in a state where it has been rotated downward. [Figure 5] Fig. 5 is a perspective view showing the structure of the working step from an obliquely upper rear angle different from that of Fig. 5. In Fig. 5, the working step is shown in a state where it has been rotated downward. [Figure 6] 6 is a perspective view showing the structure of the working step from an obliquely upper rear side, in which the working step is shown in a state where it is closed upward. [Figure 7] Figure 7 is a front view of brackets 6a and 6b used in this embodiment, where Figure 7(a) is a front view of bracket 6a, and Figure 7(b) is a front view of bracket 6b. [Figure 8] 8A and 8B are diagrams showing the effects of this embodiment, where Fig. 8(a) is a diagram showing the structure of a conventional work step, and Fig. 8(b) is a diagram showing the structure of a work step of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] As shown in Figures 1 to 3, the road paving machine 1 is equipped with a screed device 1a for spreading and leveling the asphalt mixture sent from the front hopper, bar feeder, and screw. The screed device 1a of the road paving machine 1 is equipped with a main bottom plate 2, a left bottom plate 3, and a right bottom plate 4. A working step structure 5 is attached to the screed device 1a.

[0023] As shown in FIG. 1, the step structure 5 can be rotated in the direction of arrow A.

[0024] As shown in Figures 2 and 3, the step structure 5 includes a bracket 6a attached to the left telescopic structure of the screed device 1a and a bracket 6b attached to the right telescopic structure. Because the left and right telescopic structures are staggered, the lengths of the brackets 6a and 6b are different. In the drawings, the left telescopic structure is at the front of the vehicle, and the right telescopic structure is at the rear of the vehicle, so bracket 6a is longer than bracket 6b (see Figure 7).

[0025] A left-side extendable step platform 7a is attached to bracket 6a via a pivotal bracket 8. A left-side extendable step platform 7b is attached to bracket 6b via a pivotal bracket 8. The central step platform 7b is pivotally attached to the screed device 1a.

[0026] The rotation structure of the step structure 5 will be described with reference to FIGS.

[0027] The left end of the left telescopic step 7a has a bent portion 7a-1.

[0028] The pivot bracket 8 is a member for pivotably connecting the left telescopic step board 7a and the bracket 6a.

[0029] It goes without saying that the size of the rotating brackets 8, 8 may also be adjusted depending on whether they are on the left or right side.

[0030] The rotating bracket 8 has a bent portion 8a that faces the bent portion 7a-1. The bent portion 8a and the bent portion 7a-1 are detachably connected by a fastening means 11a (only one is visible in FIG. 4, but multiple fastening means 11a may be provided as needed).

[0031] The pivoting bracket 8 is pivotally connected to the bracket 6a by fastening means 9a and 9b. The fastening means 9a is attached to a groove 10b in the bracket 6a. The fastening means 9b is attached to a groove 10a in the bracket 6a.

[0032] The bracket 6b side has the same structure as the bracket 6a side, so the above description is used to illustrate and explain the bracket 6b side, and detailed explanation will be omitted.

[0033] As shown in FIG. 5, the central step platform 7b is attached to left and right rotary shafts 12a and 12b provided on the housing of the screed device 1a.

[0034] As shown in Figures 4 and 5, the left and right extendable step stools 7a and 7c can be slid and stored inside the central step stool 7b.

[0035] As shown in Figures 2 and 3, bracket 6a and bracket 6b are connected to the left telescopic step platform 7a and the right telescopic step platform 7c via pivoting bracket 8, respectively. When the screed is extended, the left telescopic step platform 7a and the right telescopic step platform 7c slide left and right to come out from the central step platform 7b.

[0036] When the screed is retracted, as shown in Figures 4 and 5, the left-side telescopic step platform 7a and the right-side telescopic step platform 7c slide into and are stored inside the central step platform 7b. At this stage, the brackets 6a, 6b and the pivoting brackets 8, 8 are connected by their respective fastening means 11a (the state shown in Figures 4 and 5).

[0037] In this state, when the fastening means 11a are removed, the connection between the pivot brackets 8, 8 and the left and right telescopic step stools 7a, 7c is released.

[0038] By loosening the fastening means 9a, 9b, the pivoting brackets 8, 8 can be pivoted upward along the grooves 10a, 10b in Figures 7(a) and 7(b). At the same time, the central step stool 7b, which houses the left telescopic step stool 7a and the right telescopic step stool 7c, can be pivoted upward around the pivot axes 12a and 12b. As a result, as shown in Figure 6, the left and right pivoting brackets 8, 8, the left telescopic step stool 7a, the right telescopic step stool 7c, and the central step stool 7b can be pivoted in the direction of arrow A in Figure 1 and folded upward for storage.

[0039] When the left-side telescopic step stool 7a, the right-side telescopic step stool 7c, and the center step stool 7b are folded downward, the brackets 6a, 6b and the pivoting brackets 8, 8 are horizontal. In the case of the conventional step shown in FIG. 8(a), the step was stored in section D shown in FIG. 1, so the area of ​​each base plate had to be reduced by the amount of section D. However, in this embodiment, the step can be stored upward when the screed is retracted, so the area of ​​the base plate can be expanded to the section D shown in FIG. 1 near the lower rear ends of the brackets 6a, 6b. As a result, as shown in FIG. 8(b), the overall area of ​​the base plates 2, 3, and 4 can be increased compared to FIG. 8(a).

[0040] Therefore, this embodiment makes it possible to maximize the area of ​​the bottom plate, and further makes it possible to store the work steps in a limited compartment.

[0041] (Variation) In the above embodiment, the connection between the pivot brackets 8,8 and the left-side telescopic step platform 7a and the right-side telescopic step platform 7c is released, but if the shape of the left-side telescopic step platform 7a and the right-side telescopic step platform 7c or the pivot brackets 8,8 is changed so as to avoid the components 13,13 present in the screed device, it is not necessary to release the connection.

[0042] The shapes of the brackets 6a, 6b and the rotating bracket 8 are not limited to those shown in the drawings, and any shape may be used as long as the rotating bracket 8 is rotatable relative to the brackets 6a, 6b. When the rotating bracket 8 is spread downward, it is sufficient that the rotating bracket 8 and the brackets 6a, 6b are horizontal.

[0043] In the above embodiment, opposing bent portions 7a-1 and 8a are used to connect the pivot brackets 8, 8 to the left and right telescopic step stools 7a, 7c, but this is not limited to this.As long as the pivot brackets 8, 8 and the left and right telescopic step stools 7a, 7c are configured to be detachably connected, the present invention is not limited to a structure using such bent portions.

[0044] The fastening means 11a for connecting the bent portion 7a-1 and the bent portion 8a may have any structure, such as a bolt or a pin.

[0045] The left-right relationship used in the above explanation may be reversed. Therefore, the left telescopic step stool 7a can be conceptually expressed as the first telescopic step stool, and the right telescopic step stool 7c can be conceptually expressed as the second telescopic step stool. Similarly, the left bottom plate 3 can be conceptually expressed as the first bottom plate, and the right bottom plate 4 as the second bottom plate. Furthermore, if the left and right are reversed, the shapes of the brackets 6a, 6b and the swivel brackets 8, 8 can also be changed appropriately.

[0046] In the above embodiment, the step structure is shown for a triple screed (a system using a main bottom plate, a left bottom plate, and a right bottom plate), but it can also be applied to a four- or more-unit telescopic screed device. That is, when the screed is retracted, the step platforms at both ends are released from the brackets 6a, 6b and the pivoting brackets 8, 8 attached to the screed device, and all of the step platforms stored in the central step platform are folded upward, and the pivoting brackets 8, 8 are also folded upward.

[0047] Although the present invention has been described in detail above, the above description is merely illustrative of the present invention in all respects and is not intended to limit its scope. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. Each of the constituent elements of the invention disclosed in this specification is considered to be an independent, stand-alone invention. Inventions in which the constituent elements are combined in any manner are also included within the scope of the present invention. [Industrial Applicability]

[0048] INDUSTRIAL APPLICABILITY The present invention relates to a road paving machine and a support structure for a work step used therein, and is industrially applicable. [Explanation of symbols]

[0049] 1. Road paving machines 1a Screed device 2 Main base plate 3 Left bottom plate (first bottom plate) 4 Right side bottom plate (second bottom plate) 5-step structure 6a Bracket (First Bracket) 6b Bracket (Second Bracket) 7a Left-side telescopic step platform (first telescopic step platform) 7a-1 Bent part 7b Central step 7c Right-side telescopic step platform (second telescopic step platform) 8 Rotating bracket (first rotating bracket, second rotating bracket) 8a Bend part 9a,9b Fastening means 10a,10b groove 11a Fastening means 12a, 12b Rotation axis

Claims

1. A support structure for a work step attached to a screed device of a road paving machine that can extend and retract the screed to the left and right, a first bracket attached to the left telescoping structure of the screed; a first pivot bracket attached to the first bracket so as to be pivotable upward; a first extendable step platform attached to the first pivot bracket and slidable to the left and right; a second bracket attached to the right telescoping structure of the screed; a second pivot bracket attached to the second bracket so as to be pivotable upward; a second extendable step platform attached to the second pivot bracket and slidable left and right; A support structure for a work step, characterized in that it comprises a central step base attached to the housing of the screed device so as to be rotatable upward.

2. When the screed device is retracted, the first extendable step platform and the second extendable step platform can be stored inside the central step platform; 2. The support structure for work steps according to claim 1, wherein the first extendable step platform, the second extendable step platform, the central step platform, the first pivot bracket, and the second pivot bracket can be rotated upward and folded for storage.

3. The connection between the first pivot bracket and the first extendable step platform is releasable, 3. The support structure for a work step according to claim 2, wherein the connection between the second pivot bracket and the second extendable step platform is releasable.

4. A support structure for a work step according to any one of claims 1 to 3, characterized in that a bottom plate of the screed device is provided up to the lower rear ends of the first and second brackets.

5. A road paving machine comprising a screed device having a support structure for a working step according to any one of claims 1 to 4.

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