WO2018136049A1

WO2018136049A1 - Screed heating element clamp

Info

Publication number: WO2018136049A1
Application number: PCT/US2017/013916
Authority: WO
Inventors: Siddartha REDDY
Original assignee: Volvo Construction Equipment Ab
Priority date: 2017-01-18
Filing date: 2017-01-18
Publication date: 2018-07-26

Abstract

An asphalt paver includes an asphalt screed, at least one heating element, at least one bracket, and a plurality of bolts. The asphalt screed includes a lower frame section releasably secured to a screed plate and an upper frame section that defines a plurality of bores. The at least one heating element is located on the screed plate. The plurality of bolts are received by the plurality of bores and generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

Description

SCREED HEATING ELEMENT CLAMP

FIELD OF THE INVENTION

The present invention relates to a screed heating element clamp.

BACKGROUND OF THE INVENTION

Asphalt pavers are typically provided with a heated screed plate that levels the asphalt during the asphalt paving process. The present invention is directed at an improved system for holding the heating element to the screed plate.

SUMMARY OF THE INVENTION

According to one embodiment of the present invention, an asphalt paver comprises an asphalt screed, at least one heating element, at least one bracket, and a plurality of bolts. The asphalt screed is provided with a bottom end that includes a lower frame section releasably secured to a screed plate and top end that includes an upper frame section that defines a plurality of bores. The at least one heating element is located on the screed plate. The plurality of bolts are received by the plurality of bores so that heads of the plurality of bolts are located at the top end of the asphalt screed and generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket the screed plate.

According to another embodiment of the present invention, a method for clamping at least one heating element to a screed plate of an asphalt paver that includes, an asphalt screed provided with a bottom end that includes a lower frame section releasably secured to a screed plate and a top end that includes an upper frame section that defines a plurality of bores, a plurality of bolts, and at least one bracket, comprises the steps of locating the at least one heating element on the screed plate, inserting the plurality of bolts into the plurality of bores so that heads of the plurality of bolts are located at the top end of the asphalt screed, tightening the plurality of bolts to generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

According to yet another embodiment of the present invention, an asphalt paver comprises an asphalt screed, at least one heating element, at least one bracket, and a plurality of bolts. The asphalt screed is provided with a lower frame section releasably secured to a screed plate and an upper frame section that defines a plurality of bores. The at least one heating element is located on the screed plate. The plurality of bolts are received by the plurality of bores and generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket the screed plate. ASPECTS

According to one aspect of the present invention, an asphalt paver includes:

an asphalt screed provided with a bottom end that includes a lower frame section releasably secured to a screed plate and a top end that includes an upper frame section that defines a plurality of bores;

at least one heating element located on the screed plate;

at least one bracket;

a plurality of bolts that:

are received by the plurality of bores so that heads of the plurality of bolts are located at the top end of the screed; and generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

Preferably, the asphalt paver further includes a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges that apply the clamp load to the at least one bracket and are releasably secured to lower ends of the bolts.

Preferably, the plurality of bolt clamping assemblies further include a plurality of flange bolts provided with external threads that cooperate with internal threads located at the lower ends of the plurality of bolts to releasably secure the flanges to the lower ends of the bolts.

Preferably, the asphalt paver further includes a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges releasably secured to lower ends of the bolts, wherein:

the plurality of flanges include first flange sections, second flange sections, and undercut sections located between the first and second flange sections; the at least one bracket defines a plurality of flange keyways that receive the plurality of flanges and include enlarged cutout sections and reduced cutout sections;

the enlarged cutout sections including widths that are greater widths of the second flange sections and the undercut sections and less than widths of the first flange sections;

the reduced cutout sections include widths that are greater than the widths of the cutout section and less than the widths of the first and second flange section; and the reduced cutout sections receive the undercut sections so that the brackets are interposed between the first and second flange section.

According to another aspect of the present invention a method for clamping at least one heating element to a screed plate of an asphalt paver that includes an asphalt screed provided with a bottom end that includes a lower frame section releasably secured to a screed plate and an top end that includes an upper frame section that defines a plurality of bores, a plurality of bolts, and at least one bracket, includes the steps of:

locating the at least one heating element on the screed plate;

inserting the plurality of bolts into the plurality of bores so that heads of the plurality of bolts are located at the top end of the asphalt screed; and tightening the plurality of bolts to generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

Preferably, the paver further includes a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges and the method further includes the steps of releasably securing the flanges to bolts after the bolts are inserted into the bores and using the flanges to apply the clamp load to the at least one bracket as the plurality of bolts are tightened.

Preferably, the plurality of bolt clamping assemblies further include a plurality of flange bolts provided with external threads and the plurality of bolts include internal threads located at the lower ends of the plurality of bolts and the method further includes the step of using the external threads on the plurality of flange bolts to cooperate with the internal threads on the plurality of bolts and releasably secure the plurality of flanges to the lower ends of the plurality of bolts.

Preferably, the paver further includes a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges that include a first flange section, a second flange section, and an undercut section located between the first and second flange sections and the at least one bracket defines a plurality of flange keyways that include enlarged cutout sections and reduced cutout sections and the method further includes the steps of:

releasably securing the plurality of flanges to lower ends of the plurality of bolts;

inserting the second flange section and the undercut section into the enlarged cutout sections of the flange keyways; moving the undercut section within the flange keyways from the enlarged cutout section to the reduced cutout section so that the reduced cutout section receives the undercut section and the at least one bracket is interposed between the first and second flange sections; and

using the plurality of flanges to apply the clamp load to the at least one bracket as the plurality of bolts are tightened.

Preferably, the method further includes the step of using the flanges to support the bracket in a spaced relationship from the heating element before the clamp load is applied.

According to another aspect of the present invention an asphalt paver includes:

an asphalt screed provided with a lower frame section releasably secured to a screed plate and an upper frame section that defines a plurality of bores;

at least one heating element located on the screed plate;

at least one bracket; and

a plurality of bolts that are received by the plurality of bores and that generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows an asphalt paver according to one embodiment.

Figure 2 shows a top perspective view of an asphalt screed according to one embodiment.

Figure 3 shows a top perspective sectional view of an asphalt screed according to one embodiment.

Figure 4 shows a side perspective view of a clamping assembly according to one embodiment.

Figure 5 shows a sectional view taken along A-A in Figure 2 of an asphalt screed according to one embodiment.

Figure 6 shows a sectional view taken along A-A in Figure 2 of an asphalt screed according to one embodiment.

Figure 7 shows a sectional view taken along A-A in Figure 2 of an asphalt screed according to one embodiment.

Figure 8 shows a sectional view taken along A-A in Figure 2 of an asphalt screed according to one embodiment.

DETAILED DESCRIPTON OF THE INVENTION Turning now to FIG. 1, an example of an asphalt paver 15 is shown. The asphalt paver 15 is configured to receive, deposit, and level asphalt mix 5 to at least partially form an asphalt pavement 7 on top of a paving surface 6. As shown therein, the asphalt paver 15 may be provided with an asphalt hopper 20, an asphalt conveyor 25, and an asphalt spreader 30. Also shown, the asphalt paver includes an asphalt screed 40 that is supported by tow arms, as at 35, and is provided with an asphalt leveling surface 45. The asphalt paver 15 may also be provided with at least one vertically reciprocating tamper (not shown) located forward of the asphalt leveling surface 45.

Those of ordinary skill in the art will appreciate that during a paving operation, asphalt mix 5 is typically loaded onto the paver 15 and temporarily held in an asphalt hopper, such as asphalt hopper 20. Those of ordinary skilled in the art will also appreciate that during a paving operation, one or more asphalt conveyors, such as asphalt conveyor 25, typically transport the asphalt mix 5 from the asphalt hopper 20 and deposit it on a paving surface, such as paving surface 6, whereat one or more asphalt spreaders, such as asphalt spreader 30, which may be in the form of one or more augers, as shown, spread the asphalt mix 5 on the paving surface 6 in a direction that is lateral with respect to a direction of travel of the paver 15. Those of ordinary skill in the art will further appreciate that the after the asphalt mix 5 is deposited on the paving surface 6 and laterally distributed on the paving surface 6 by the asphalt spreader 30, that as the paver 15 travels along the paving surface 6, for example by a track assembly or wheels, as at 16, that the asphalt mix 5 is typically partially compacted by the reciprocating ramming action of the at least one tamper and that the asphalt leveling surface 42 contacts and levels the asphalt mix 5, whereby a freshly laid asphalt pavement 7 is formed on the paving surface 6.

Turning now to FIGS. 5-8 an example of an asphalt screed 40 according to one embodiment is illustrated. As shown, located at the bottom end 40c of the asphalt screed 40 is a lower frame section 44a releasably secured to screed plate 41. Located on the underside of the screed plate 41 is the asphalt leveling surface 42. The screed plate 41 is also provided with an upper side surface 43 opposite the asphalt leveling surface 45. The upper side surface 43 typically includes a plurality of threaded studs, as at S, that cooperate with nuts, as at N, to releasably connect the screed plate 41 to the lower frame section 44a.

The asphalt screed 40 is also provided with a top end 40a, opposite the bottom end 40b, that includes an upper frame section 44b having an underside surface 45 and an upper side surface 46 opposite the underside surface 45. The upper side surface 46 is oriented to face towards an exterior 40b of the asphalt screed 40. The underside surface 45 is oriented to face towards the upper side surface 43 of the screed plate 41. As shown, the interior 40a of the asphalt screed 40 is defined between upper frame section 44b and the screed plate 41.

According to one aspect of the present embodiment, the upper frame section 44b is configured to receive a plurality of threaded bolts 80 provided with a head 81 that is configured to receive torque and rotate the bolt. According to one aspect of the present embodiment, the head is located at the top end 40aof the asphalt screed 40.

As shown in FIG. 5-8, the upper frame section 44b defines a plurality of bores 47 that extend between the underside surface 45 and the upper side surface 46. According to one aspect of the present embodiment, the bores 47 receive the plurality of bolts 80, which are inserted into the bores 47. Also shown, the bolts 80 are provided with an external surface that is at least partially threaded, as at 81. In the embodiment shown, the upper end 80a of the bolts 80 may be threaded as at 81 and the external surface at the lower end 80b of the bolts 80 may be unthreaded.

According to one aspect of the present embodiment, the upper frame section 44b may include a plurality of threads, as at 45a. According to one aspect of the present embodiment, the bores 47 may include a plurality of threads, as at 45a. According to another aspect of the present embodiment, the interior 40d of the asphalt screed 40 may include a plurality of threads, as at 45b.

Those of ordinary skill in the art will appreciate that as torque is applied to the head 81 on the bolts 80, the threads 82 mate with threads, such as, for example, threads 45a or 45b. Advantageously, as this occurs and the bolt 80 is continued to be tightened the bolt 80 eventually extends from the top side 40a to the bottom side 40b of the asphalt screed 40 and exerts a clamp load that is applied to at least one bracket 60. Advantageously, the clamp load applied to the bracket 60 clamps at least one heating element 70 between the bracket 60 and the upper side surface 43 of the screed plate 41 and holds the at least one heating element 70 in place. Advantageously, the head 81 is externally located, relative to the interior 40d of the asphalt screed 40, which allows for readily accessibility to the heads 81 on bolts 80 along at top end 40a of the asphalt screed 40 for purposes of clamping and unclamping the one or more heating elements 70 to the screed plate 41 so that heat can be applied to the screed plate 41. Those of ordinary skill in the art will appreciate that clamping the one or more heating elements 70 to the screed plate 41 allows for heating of the screed plate 41 during a paving operation which assists in the prevention of asphalt mix cooling and adhering to the screed plate 41. While it is in within the scope of the present embodiment for the plurality of bolts 80 as described above to generate a clamp load that is applied to the one or more brackets 60 in various ways, including such as, for example, by directly applying a clamp load to the one or more brackets 60, in the presently preferred embodiment, the bolts 80 are a component of a plurality of bolt clamping assemblies 75 (FIG. 4) that further include flanges 90.

According to one aspect of the present embodiment, the flanges 90 are releasably secured to lower ends 80b of the bolts 80. Within the scope of the present embodiment, the flanges 90 may be releasably secured to the lower end 80b of the bolts 80 in numerous ways. By way of example, the lower end 80b of the bolts may be threaded and may cooperate with a nut (not shown) or a threaded flange (not shown) to releasably secure the flange at the lower end 80b of the bolts 80. As shown best in FIGS. 5-8, in the presently preferred embodiment, the preferred bolt 80 of clamping assemblies 75 is provided with threads, such as internal threads at 83, which releasably secure a flange 90 to the bolt 80. As shown the internal threads 83 are located in a cavity 84 that extends from a lower end 80b of the bolt 80. Also shown, a flange bolt 87 includes external threads, as at 89, may cooperate with the internal threads 83 of bolt 80 to releasably secure the flange 88 at the lower end 80b of the bolt 80. The flange bolt 87 includes a head 88 and as shown in FIG. 4, when the clamping assembly 75 is assembled the flange bolt 87 extends through a central bore 90a of the flange

90 and the flange 90 is located between the head 88 of the flange bolt 87 and the internal threads 83 of the bolt 80.

According to another aspect of the present embodiment the flanges 90 apply the clamp load to the bracket 60. According to yet another aspect of the present embodiment the flanges 90 may support the bracket 60 in a spaced relationship from the heating element 70 before the clamp load is applied and then vertically lowered onto the heating element 70 after the heating element is properly on the screed plate 41.

Turning now to FIG. 4, in the present embodiment, the flange 90 includes at least one flange section 91 and preferably first and second flange sections 91, 92 and an undercut section 93. As shown the flange section 91 is located at an upper end of the flange 90, the second flange section 92 is located at a lower end of the flange 90, and the undercut section 93 is defines a groove 93a located between flange section 91 and second flange section 92.

As shown best in FIG. 4, the flange section 91 is provided with a width W2 that is greater than the width Wl of the bolt 80. The enlarged width W2 of the flange section 91 increases the surface area of the clamp load applied to the brackets 60 by the flange section

91 relative to the width Wl of the bolt 80. Also shown, the second flange section 92 is provided with a width W3 that measures less than the width W2 of the flange section 91 and the undercut section 93 is provided with a width W4 that measures less than widths W2 and W3.

As shown in FIGS. 3 and 5-8, the bracket 60 define a plurality of flange keyways 61 that receive the plurality of flanges 90 of the bolt clamping assemblies 75. As shown the each flange keyway 61 preferably includes an enlarged cutout section 62 and a reduced cutout section 63.

The enlarged width section is provided with width W5. According to one aspect of the present embodiment the width W5 measures greater than the width W3 of the second flange section 92. According to another aspect of the present embodiment the width W5 measures greater than the width W4 of the undercut section 93. According to still yet another aspect of the present embodiment, the width W5 measures less than the width W2 of the flange section 91.

The reduced cutout section 63 is provided with width W6. According to one aspect of the present embodiment, the width W6 measures less than the width W5. According to another aspect of the present embodiment, the width W6 measures less than the width W3 of the second flange section 92. According to another aspect of the present embodiment the width W6 measures greater than the width W4 of the undercut section 93. According to still yet another aspect of the present embodiment, the width W6 measures less than the width W2 of the flange section 91.

According to one aspect of the present embodiment, as FIGS. 5-7 best illustrate, to connect the clamp assemblies 75 to the brackets 60, the flanges 90 move within the keyways 61 from the enlarged cutout section 62 to the reduced cutout section 63. According to another aspect of the present embodiment, as FIGS. 5-7 best illustrate, to connect the clamp assemblies to the brackets 60, the undercut section 93 of the flanges 90 moves within the keyways 61 from the enlarged cutout section 62 to the reduced cutout section 63.

Turning now to FIGS. 5 and 6, to initially connect the clamp assemblies 75 to the brackets 60, the flanges 90 are inserted into the enlarged cutout section 62. As this occurs, the second flange section 92 and undercut section are inserted into the enlarged cutout section 62. Whereas the width W5 of the enlarged cutout section 62 receives the widths W3 of the second flange section 92 and the width W4 of the undercut section 93, the smaller width W5 of the enlarged cutout section 62 prevents the flange section 91 from entering or passing through the enlarged cutout section 62. Turning now to FIG. 7, after the undercut section 93 is inserted into the enlarged cutout section 62, relative horizontal movement between the flange 90 and the bracket 60 positions the flange 90 within the reduced cutout section 63. As this occurs, the reduced cutout section 63 receives the undercut section 93 so that the brackets 60 are interposed between the flange section 91 and second flange section 92 whereby the reduced cutout section 63 is located within the groove 93a. Advantageously, as shown in FIG. 7, once the clamp assemblies 75 are connected to a bracket 60, the bracket 60 may be seated on and supported by the second flange section 93 and in a vertically spaced manner above one or more heating elements 70.

Turning now to FIG. 8, once the heating element 70 is located on the screed plate 41, the bolts 80, having heads 81, which are easily accessible via the upper side surface 46 of the upper frame section 44b, may be tightened to lower the bracket 60 so that one or more heating elements 70 are clamped between the bracket 60 and the screed plate 41.

Advantageously, in the present embodiment the clamp load generated by the bolts 80 is directed downwards towards the upper side surface 43 of the screed plate 41 to press and hold the heating element 70 into contact with the upper side surface 43 of the screed plate 41. Advantageously, the clamp load will directly oppose and resists forces or vibrations tending to urge the heating element 70 away from the upper side surface 43.

The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the invention. The present description depicts specific examples to teach those skilled in the art how to make and use the best mode of the invention. Those skilled in the art will appreciate variations from these examples that fall within the scope of the invention.

Persons skilled in the art will recognize that certain elements of the above-described embodiments and examples may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the invention. It will also be apparent to those of ordinary skill in the art that the above-described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the invention. Thus, although specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. Accordingly, the scope of the invention is determined from the appended claims and equivalents thereof.

Claims

I CLAIM:

1. An asphalt paver comprising:

at least one heating element located on the screed plate;

at least one bracket;

a plurality of bolts that:

are received by the plurality of bores so that heads of the plurality of bolts are located at the top end of the asphalt screed; and

generate a clamp load that is applied to the at least one bracket to clamp the at least one heating element between the at least one bracket and the screed plate.

2. The asphalt paver according to claim 1, further comprising a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges that apply the clamp load to the at least one bracket and are releasably secured to lower ends of the bolts.

3. The asphalt paver according to claim 2, wherein the plurality of bolt clamping assemblies further comprise a plurality of flange bolts provided with external threads that cooperate with internal threads located at the lower ends of the plurality of bolts to releasably secure the flanges to the lower ends of the bolts.

4. The asphalt paver according to claim 1, further comprising a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges releasably secured to lower ends of the bolts, wherein:

the enlarged cutout sections including widths that are greater widths of the second flange sections and the undercut sections and less than widths of the first flange sections; the reduced cutout sections include widths that are greater than the widths of the cutout section and less than the widths of the first and second flange section; and

the reduced cutout sections receive the undercut sections so that the brackets are interposed between the first and second flange section.

5. A method for clamping at least one heating element to a screed plate of an asphalt paver that includes an asphalt screed provided with a bottom end that includes a lower frame section releasably secured to a screed plate and a top end that includes an upper frame section that defines a plurality of bores, a plurality of bolts, and a bracket, the method comprising the steps of:

locating the at least one heating element on the screed plate;

6. The method for clamping at least one heating element to a screed plate of an asphalt paver according to claim 5, wherein the paver further comprises a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges, the method further comprising the steps of:

releasably securing the flanges to bolts after the bolts are inserted into the bores; and using the flanges to apply the clamp load to the at least one bracket as the plurality of bolts are tightened.

7. The asphalt paver according to claim 6, wherein the plurality of bolt clamping assemblies further comprise a plurality of flange bolts provided with external threads and the plurality of bolts include internal threads located at the lower ends of the plurality of bolts, the method further comprising the step of:

using the external threads on the plurality of flange bolts to cooperate with the internal threads on the plurality of bolts and releasably secure the plurality of flanges to the lower ends of the plurality of bolts.

8. The method for clamping at least one heating element to a screed plate of an asphalt paver according to claim 5, wherein the paver further includes a plurality of bolt clamping assemblies that include the plurality of bolts and a plurality of flanges that include a first flange section, a second flange section, and an undercut section located between the first and second flange sections and the at least one bracket defines a plurality of flange keyways that include enlarged cutout sections and reduced cutout sections, the method further comprising the steps of:

inserting the second flange section and the undercut section into the enlarged cutout sections of the flange keyways;

moving the undercut section within the flange keyways from the enlarged cutout section to the reduced cutout section so that the reduced cutout section receives the undercut section and the at least one bracket is interposed between the first and second flange sections; and

9. The method for clamping at least one heating element to a screed plate according to claim 5, further comprising the step of using the flanges to support the bracket in a spaced relationship from the heating element before the clamp load is applied.

10. An asphalt paver comprising:

at least one heating element located on the screed plate;

at least one bracket; and