SPRAY ASSEMBLY FOR A WORKING MACHINE EMPLOYING DIRECT ACTING VALVES

Abstract

A spray assembly for a working machine that includes a fluid storage tank includes a plurality of nozzle assemblies, each of which includes a direct acting valve. The spray assembly also includes a controller that is operatively connected to each of the direct acting valves for controlling the opening and closing of the direct acting valves, and a selector that is operatively connected to the controller. The selector may be employed by an operator of the working machine to selectively operate one or more of the direct acting valves in order to provide a desired spray pattern of fluid from the fluid storage tank.

Claims

1. A spray assembly for a working machine that includes a fluid storage tank and is adapted for operation on a roadway, said spray assembly being in fluid communication with the fluid storage tank and further comprising: (a) a plurality of nozzle assemblies, each of which comprises a direct acting valve; (b) a controller that is operatively connected to each of the direct acting valves for controlling the opening and closing thereof; (c) a selector that is operatively connected to the controller, which selector may be employed by an operator of the working machine to selectively operate one or more of the direct acting valves in order to provide a desired spray pattern of fluid from the fluid storage tank onto the roadway.

2. The spray assembly of claim 1 wherein each of the direct acting valves is a direct acting poppet valve that is enabled by a linear solenoid.

3. The spray assembly of claim 2 wherein the controller is adapted to employ pulse-width modulation current control to reduce the current required to hold the direct acting poppet valves open.

4. The spray assembly of claim 2: (a) which includes a support beam that is attached to the frame of the working machine; (b) which includes a power source for the controller; (c) wherein each of the nozzle assemblies: (i) is mounted on the support beam; (ii) includes a solenoid switch assembly and a valve assembly; (d) wherein the controller comprises: (i) a spray control; (ii) an input module that is operatively connected to the solenoid switch assembly of each nozzle assembly and to the spray control, said input module being adapted to determine if the valve assembly of each nozzle assembly is open or closed; (iii) an output module that is operatively connected to the spray assembly and to the power source, said output module being adapted to energize the solenoid switch assembly of each nozzle assembly in the spray assembly.

5. The spray assembly of claim 4 wherein the input module is operatively connected to one or more sensors for measuring operating parameters of the spray assembly.

6. The spray assembly of claim 4 wherein each valve assembly comprises: (a) a nozzle housing which includes a poppet bushing; (b) a valve housing that is in fluid communication with the fluid storage tank of the working machine and the nozzle housing; (c) a poppet shaft having an upper end and a lower end; (d) a poppet which is attached to the lower end of the poppet shaft; (e) a plunger which is attached to the upper end of the poppet shaft; (f) a return spring surrounding the poppet shaft and adapted to hold the poppet in abutment with the poppet bushing in the nozzle housing when the solenoid switch assembly is not energized.

7. The spray assembly of claim 6 wherein each solenoid switch assembly comprises: (a) a switch conductor that is electrically connected to the power source; (b) a switch pin insulator that is operatively connected to the switch conductor; (c) a switch pin that is electrically connected to the switch conductor; (d) a coil that surrounds the plunger of the valve assembly associated therewith, said coil being electrically connected to the switch pin; wherein the controller is adapted to energize the solenoid switch assembly to cause electricity from the power source to flow through the switch conductor and the switch pin to energize the coil, thereby creating a magnetic field which causes the plunger to be drawn upwardly so that the poppet is not in abutment with the poppet housing.

8. The spray assembly of claim 7 wherein each valve assembly includes an inlet port in the valve housing that is in fluid communication with the fluid storage tank of the working machine.

9. The spray assembly of claim 7 wherein each valve assembly includes a travel stop that is located so as to be engaged by the upper end of the plunger when the controller causes electricity to energize the coil to generate a magnetic field to draw the plunger upwardly.

10. The spray assembly of claim 7 wherein each valve assembly includes a shaft seal that prevents fluid from leaking upwardly around the poppet shaft when the plunger is drawn upwardly so that the poppet is not in abutment with the poppet housing.

11. A method for operating a working machine including a fluid storage tank on a roadway, said method comprising: (a) providing a spray assembly that is in fluid communication with the fluid storage tank, said spray assembly further comprising: (i) a plurality of nozzle assemblies, each of which includes a direct acting valve; (ii) a controller that is operatively connected to each of the direct acting valves for controlling the opening and closing thereof; (iii) a selector that is operatively connected to the controller, which selector may be employed by an operator of the working machine to selectively operate one or more of the direct acting valves in order to provide a desired spray pattern of fluid from the fluid storage tank onto the roadway; (b) employing the selector to select one or more of the direct acting valves for operation in order to provide a desired spray pattern on the roadway.

12. The method of claim 11 which includes employing the selector to simultaneously operate all of the direct acting valves in the spray assembly.

13. The method of claim 11 which includes employing the selector to simultaneously operate adjacent pairs of direct acting valves in the spray assembly, with a single direct acting valve between each adjacent pair of operating direct acting valves turned off.

14. The method of claim 11 which includes employing the selector to simultaneously operate half of the direct acting valves in the spray assembly, with a direct acting valve adjacent to each operating direct acting valve turned off.

15. The method of claim 11 which includes employing the selector to simultaneously operate one-third of the direct acting valves in the spray assembly, with a pair of direct acting valves adjacent to each operating direct acting valve turned off.

16. The method of claim 11 which includes providing a spray assembly in which each of the direct acting valves is a direct acting poppet valve that is enabled by a linear solenoid.

17. The method of claim 16 which includes providing a spray assembly having a controller which comprises: (a) a spray control; (b) an input module that is operatively connected to the solenoid switch assembly of each nozzle assembly and to the spray control, said input module being adapted to determine if the valve assembly of each nozzle assembly is open or closed; (c) an output module that is operatively connected to the spray assembly and to a power source, said output module being adapted to energize the solenoid switch assembly of each nozzle assembly in the spray assembly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The presently preferred embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which:

[0026] FIG. 1 is a side view of an asphalt paving machine to which a first embodiment of the invention has been applied.

[0027] FIG. 2 is a perspective view of a first embodiment of the spray assembly shown in FIG. 1.

[0028] FIG. 3 is a side view of a direct acting poppet valve assembly that is employed in connection with the invention.

[0029] FIG. 4 is a sectional view of the direct acting poppet valve assembly of FIG. 3, taken through the line 4-4 of FIG. 3, which shows the valve assembly in a closed position.

[0030] FIG. 5 is a front view of the first embodiment of a spray assembly of the invention that is illustrated in FIG. 2, showing its use in applying a first spray pattern.

[0031] FIG. 6 is a front view of the first embodiment of a spray assembly of the invention that is illustrated in FIG. 2, showing its use in applying a second spray pattern.

[0032] FIG. 7 is a front view of the first embodiment of a spray assembly of the invention that is illustrated in FIG. 2, showing its use in applying a third spray pattern.

[0033] FIG. 8 is a front view of the first embodiment of a spray assembly of the invention that is illustrated in FIG. 2, showing its use in applying a fourth spray pattern.

[0034] FIG. 9 is a front view of a second embodiment of a spray assembly of the invention, showing its use in applying a fifth spray pattern.

[0035] FIG. 10 is a front view of a second embodiment of a spray assembly of the invention, showing its use in applying a sixth spray pattern.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0036] This description of the preferred embodiments of the invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. The drawings are not necessarily to scale, and certain features of the invention may be shown exaggerated in scale or in somewhat schematic form in the interest of clarity and conciseness.

[0037] The invention comprises a spray assembly for use in connection with a working machine such as asphalt paving machine 12 shown in FIG. 1. As shown therein, paving machine 12 includes a track drive system 14 that is driven by an engine (not shown, but housed in engine compartment 16) so as to move in the working (or paving) direction indicated by arrow 18. Paving machine 12 also includes gravity-fed hopper 20 that is adapted to receive a quantity of asphalt paving material from a delivery truck or material transfer vehicle (not shown). A conventional conveyor (also not shown) is mounted in the bottom of hopper 20 and adapted to convey asphalt paving material from hopper 20 to transverse distributing auger 22 which operates to distribute the asphalt paving material across the width of the roadway or portion thereof to be paved. Floating screed 24 is located behind the distributing auger and adapted to level and compact the asphalt paving material to form an asphalt mat. Asphalt paving machine 12 also includes fluid storage tank 26 for tack material, which fluid storage tank is in fluid communication with spray assembly 28. As would be appreciated by those having ordinary skill in the art to which the invention relates, this fluid communication comprises a fluid circuit between fluid storage tank 26 and spray assembly 28 which includes a pump and suitable piping or hoses to convey the tack material from the storage tank to the spray assembly.

[0038] Referring now to FIG. 2, spray assembly 28 is attached to the frame of machine 12 and includes twenty-four nozzle assemblies 30 that are mounted onto support beam 32. Also included in the invention is a controller comprised of input module 34, output module 36, and spray control 38. Input module 34 and output module 36 may be located near spray assembly 28 and operatively connected to spray control 38 which is located in operator's control panel 40 in operator's station 41 (see FIG. 1). Input module 34 is operatively connected to solenoid switch assembly 42 of each nozzle assembly 30 of spray assembly 28 and to spray control 38, and is adapted to determine if the valve assembly associated with each nozzle assembly 30 is open or closed and to communicate this information to an operator of machine 12. In a preferred embodiment of the invention, input module 34 is also operatively connected to various sensors (not shown) in the spray assembly, such as sensors that measure fluid temperature, pressure, flow rate and other operating parameters in the system, and to spray control 38. In this preferred embodiment, input module 34 is adapted to provide information about these system parameters to a machine operator located in operator's station 41. Output module 36 is operatively connected to a power source such as battery 43, and is adapted to energize the various solenoid switch assemblies in spray assembly 28. Output module 36 is also operatively connected to spray control 38 to allow an operator of machine 12 to control the activation of the various solenoid switch assemblies in spray assembly 28.

[0039] Nozzle assembly 30 is shown in more detail in FIGS. 3 and 4. As shown therein, nozzle assembly 30 comprises a direct acting valve which includes solenoid switch assembly 42 and a valve assembly comprising valve housing 44 and nozzle housing 45. As best shown in FIG. 4, this direct acting valve comprises a direct acting poppet valve that is enabled by a linear solenoid. Solenoid switch assembly 42 includes switch pin insulator 46 which is operatively attached to switch conductor 47. Switch conductor 47 is electrically connected to power source 43, and switch pin 48 is electrically connected to switch conductor 47 to provide a path for electricity from power source 43 to coil 50. As shown in FIG. 4, the solenoid switch assembly is not energized, so that return spring 52 surrounding poppet shaft 54 holds poppet 56, which is attached to the lower end of the poppet shaft, in abutment with poppet bushing 58 in nozzle housing 45, thereby closing the valve. When the controller causes electricity to flow from power source 43 through switch conductor 47 and switch pin 48 to energize coil 50, plunger 60, which is attached to the upper end of poppet shaft 54, is drawn upwardly by the magnetic field generated by the coil until its upper end abuts travel stop 62. This causes poppet 56 to withdraw from poppet bushing 58, thus allowing asphalt emulsion or another fluid to enter valve housing 44 through inlet ports 64 under pressure sufficient to discharge it out the bottom of nozzle housing 45. Shaft seal 66 prevents fluid from leaking upwardly around poppet shaft 54.

[0040] Since input module 34 of the controller is operatively connected to each nozzle assembly 30, the nozzle assemblies can be operated to produce various spray configurations. Thus, FIG. 5 illustrates the simultaneous operation of all of the nozzle assemblies in spray assembly 28 in order to produce a triple-overlay spray configuration. FIG. 6 shows the simultaneous operation of pairs of nozzle assemblies with a single nozzle assembly between each pair turned off to produce spray coverage similar to that obtained by the operation illustrated in FIG. 5. In the example of FIG. 6, the controller generates a similar spray pattern as that of the operation of the FIG. 5 configuration by increasing the fluid pressure through ⅔ of the nozzle assemblies (i.e. with ⅓ of the nozzle assemblies turned off). Similarly, FIG. 7 illustrates the simultaneous operation of alternating nozzle assemblies. In this configuration, the controller may create the same fluid flow rate as that obtained by the operating configuration of FIG. 5 with only half the nozzle assemblies of the configuration of FIG. 5 being operated, by increasing the fluid pressure through the operating nozzle assemblies. FIG. 8 illustrates the simultaneous operation of ⅓ of the nozzle assemblies, with a pair of non-operating nozzle assemblies adjacent to each operating nozzle assembly. In this configuration, the controller may generate the same fluid flow rate as that obtained by the operating configuration of FIG. 5 with only ⅓ of the nozzle assemblies of the configuration of FIG. 5 being operated, by increasing the fluid pressure through the operating nozzle assemblies.

[0041] FIGS. 9 and 10 illustrate an alternative spray assembly 128 which has fifteen nozzle assemblies 30 spaced along support beam 132. FIG. 9 illustrates the spray pattern that may be obtained when all of the nozzle assemblies are operated simultaneously, and FIG. 10 illustrates that which may be obtained when only half the nozzle assemblies are simultaneously operated, with a non-operating nozzle assembly adjacent to each operating nozzle assembly.

[0042] The invention provides for direct electrical actuation of the valves associated with spray assemblies for working machines. By avoiding pilot-control valves and the fluid piping and components associated with such conventional systems, the invention greatly simplifies the design of the spray assembly and gives the designer the flexibility to locate the control components for the spray assembly closer to the valves, thereby keeping the wiring between the controller and the valves shorter.

[0043] Although this description contains many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments thereof, as well as the best mode contemplated by the inventor of carrying out the invention. The invention, as described and claimed herein, is susceptible to various modifications and adaptations as would be appreciated by those having ordinary skill in the art to which the invention relates.