Pavement Surfacing Machine With Vacuum Water Recovery System

Abstract

A pavement surfacing machine having a vacuum system for recovering the water used to cool and to lay the dust produced by the rotary surfacing unit of the machine, which unit comprises transversely spaced circular saws for cutting grooves in the pavement. Cuttings vacuumed up with the water are separated therefrom and the water is then reused. This minimizes the amount of water which must be transported to the job. The vacuum assembly includes a pair of vacuum head means which are disposed parallel to and one on either side of the saws. A shroud having a pavement engaging skirt surrounds the vacuum head means. The entire vacuum assembly is suspended from the machine by flexible means whereby the vacuum assembly may float relative to the saws.

Description

BACKGROUND OF INVENTION

The invention contemplates a self-propelled, vehicle-type pavement surfacing machine comprising: frame means having longitudinally spaced front and rear ends; front wheel means connected to and supporting the frame means adjacent the front end thereof; rear wheel means connected to and supporting the frame means adjacent the rear end thereof; transversely extending rotary surfacing means carried by the frame means between the front and rear wheel means, and rotatable about a transverse axis, for performing a surfacing operation on pavement over which the machine runs, which surfacing operation may be a grooving operation, or a grooving and leveling operation, or the like; power means carried by the frame means; means connecting the power means to the rotary surfacing means for driving the rotary surfacing means; means for delivering water to a transversely extending zone of engagement between the rotary surfacing means and the pavement to cool the rotary surfacing means and to lay dust produced thereby; and propelling means connecting the power means to at least one of the wheel means for propelling the machine.

Pavement surfacing machines of the foregoing general type are disclosed in my U.S. Pat. No. 3,195,957, issued July 20, 1965, No. Re. 25,838, reissued Aug. 10, 1965, No. 3,201,173, issued Aug. 17, 1965, No. 3,208,796, issued Sept. 28, 1965, No. 3,269,775, issued Aug. 30, 1966, and No. 3,272,560, issued Sept. 13, 1966, and in U.S. Pat. No. 3,407,005, issued Oct. 22, 1968 to Glen E. Simms and David E. Cook.

SUMMARY AND OBJECTS OF INVENTION

With the foregoing as background, a primary object of the present invention is to provide a vacuum system for recovering most of the water delivered to the zone of engagement between the rotary surfacing means and the pavement, and a separating system for removing virtually all of the cuttings, and other solids, picked up by the vacuum recovery system so that the water may be reused.

Recovering the water used for cooling and dust laying purposes, and rendering it suitable for reuse, are important features of the invention since they minimize the amount of water which must be transported to the job site. The significance of this will be appreciated when it is pointed out that a typical pavement surfacing machine of the type under consideration consumes water at a rate, for example, of the order of 30 gallons per minute. By recovering most, e.g., 90 percent, of this water and rendering it suitable for reuse, a great deal of expense in obtaining and transporting water to the job site is avoided.

Further, any water left on the pavement, which may be an airport runway, or a highway, represents a hazard when the pavement is returned to use. The present invention virtually eliminates this hazard by picking up most of the water. Another benefit of the present invention is that a substantial proportion of the cuttings removed by the rotary surfacing means, which cuttings are mostly dust, is trapped in the separating system to prevent its being blown about the countryside after it dries.

Another and important object of the invention is to provide a vacuum recovery system which includes transversely extending, downwardly facing vacuum head means paralleling the rotary surfacing means, and spaced longitudinally from the rotary surfacing means in the direction of longitudinal movement of the rotary surfacing means through a zone of engagement between the rotary surfacing means and the pavement, whereby the rotary surfacing means propels water toward this vacuum head means for recovery. In other words, the vacuum head means mentioned is positioned in the path of water centrifugally thrown from the rotary surfacing means.

Another object of the invention is to provide a second transversely extending, downwardly facing vacuum head means on the opposite side of the rotary surfacing means from the first vacuum head means, the second vacuum head means picking up any water which is missed by the first vacuum head means, or which runs along any grooves formed by the rotary surfacing means to the opposite side thereof.

Still another object of the invention is to provide shroud means surrounding the rotary surfacing means, the water-delivering means and the vacuum head means, and having depending skirt means engageable with the pavement. This shroud means closely confines the water and cuttings to the area served by the two vacuum head means.

Another object of the invention is to provide means for quickly and efficiently separating cuttings, and other solids, from the recovered water to render the water suitable for prompt reuse.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results which will be evident to those skilled in the pavement surfacing art in the light of this disclosure, may be achieved with the exemplary embodiment of the invention described in detail hereinafter and illustrated in the accompanying drawings.

DESCRIPTION OF DRAWINGS

FIG. 1 is a side elevational view on a reduced scale of a pavement surfacing machine equipped with the water recovery and separator system of the invention;

FIG. 2 is a diagrammatic view illustrating the flow of water, solids and air through the recovery and separator system;

FIG. 3 is a fragmentary view, partially in side elevation and partially in vertical section, duplicating a portion of FIG. 1 on an enlarged scale;

FIG. 4 is an enlarged, fragmentary, horizontal sectional view taken as indicated by the arrowed line 4-4 of FIG. 3;

FIG. 5 is a fragmentary perspective view of a portion of the vacuum recovery system of the invention;

FIG. 6 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 6-6 of FIG. 5;

FIG. 7 is a horizontal sectional view taken as indicated by the arrowed line 7-7 of FIG. 3; and

FIG. 8 is a vertical sectional view through a tank truck forming part of the water separator system.

DETAILED DESCRIPTION OF INVENTION

Illustrated in the drawings is a pavement surfacing machine 10 which is identical in all respects essential to the present invention to that disclosed in the aforementioned Simms-Cook patent. Consequently, the machine 10 will be described only generally herein.

Briefly, the pavement surfacing machine 10 includes a main frame or frame means 12 having longitudinally spaced front and rear ends respectively supported by front wheel means 14 and rear wheel means 16. Carried by the main frame 12 intermediate the front and rear wheel means 14 and 16 is a transversely extending rotary surfacing means 18 rotatable about a transverse axis. The main frame 12 also carries power means 20, preferably comprising an internal combustion engine 22, for driving the rotary surfacing means 18 and for propelling the machine 10. More particularly, the engine 22 may drive a hydraulic pump for delivering fluid under pressure to a hydraulic motor connected to one of the wheel means, such as the hydraulic motor 24, FIG. 3, connected to the rear wheel means 16. The rotary surfacing means 18 may be driven mechanically by belt means 26, FIG. 3, connecting the rotary surfacing means to the engine 22.

The rotary surfacing means 18 may be of the type disclosed in the aforementioned patents. Thus, it may include a transverse shaft rotatably mounted on the main frame 12 and carrying transversely spaced cutting or sawing blades 28, the peripheries of which carry an abrasive material, such as diamond particles or dust. Such blades cut transversely spaced grooves in the pavement, which grooves are of constant depth when merely grooving the pavement to increase its skid resistance, and are of varying depth when leveling the pavement to remove bumps therefrom in addition. The manner in which the pavement surfacing machine 10 may be used for grooving alone, or for grooving and leveling combined, is fully disclosed in the aforementioned Simms-Cook patent so that no further description herein is necessary.

The pavement surfacing machine 10 includes means for delivering water to a transversely extending zone of engagement between the rotary surfacing means 18 and the pavement, such water delivering means being shown in FIGS. 2 and 3 as comprising two transversely extending sprayers 30 paralleling and spaced longitudinally from the rotary surfacing means 18. More particularly, one of the sprayers 30 is located forwardly of the rotary surfacing means 18 and sprays rearwardly towards the transverse zone of engagement between the rotary surfacing means and the pavement. The other sprayer 30 is located rearwardly of the rotary surfacing means 18 and sprays forwardly toward the transverse zone of engagement. Recovered water, plus whatever makeup water is required, is delivered to the sprayers 30 in a manner to be described hereinafter.

Two transversely extending, downwardly facing vacuum heads or vacuum head means 32 and 34 are located forwardly and rearwardly, respectively, of the rotary surfacing means 18 in parallel relation therewith. The vacuum heads 32 and 34 preferably comprise simply transverse tubes having closed ends and respectively having downwardly facing slots 36 and 38 extending substantially the full lengths thereof. The vacuum heads 32 and 34 are respectively carried by transversely spaced skids 40 and 42 engageable with the pavement.

A vacuum means designated generally by the numeral 44 is connected to the vacuum heads 32 and 34 and causes them to pick up water from the pavement therebeneath. The vacuum means 44 includes, as one of its elements, a tubular yoke 46 having a transversely extending tubular member 48 mounted on the main frame 12 at its rearward end. Extending forwardly from the respective ends of the transverse tubular member 48 are tubular arms 50 having their forward ends connected to the respective ends of the vacuum heads 32 and 34 by flexible hoses 52 and 54.

In the particular construction illustrated, the hoses 52 and 54 are all the same diameter, and there are four of the hoses 52 and only two of the hoses 54. Considering the reason for this, the rotary surfacing means 18 rotates, as shown in FIG. 2, in a direction such that its periphery moves forwardly and upwardly, relative to the direction of travel of the machine 10, through a transversely extending zone of engagement with the pavement. Consequently, the major portion of the water delivered to the zone of engagement between the rotary surfacing means 18 and the pavement is thrown forwardly toward the front vacuum head 32 by the rotary surfacing means. For this reason, there are four of the hoses 52 connected to the front vacuum head 32 since more water must be picked up by this vacuum head. The rear vacuum head 34 picks up water missed by the front vacuum head, as well as water which may be displaced rearwardly toward the rear vacuum head by the rotary surfacing means, or which may flow rearwardly toward the rear vacuum head in grooves cut by the saws 28. However, since the rear vacuum head 34 picks up less water than the front vacuum head 32, the capacity of the rear hoses 54 does not need to be as large as that of the front hoses 52.

The vacuum heads 32 and 34 are suitably mounted on a rectangular frame 56 which encompasses the lower portion of the rotary surfacing means 18, the sprayers 30 and the two vacuum heads 32 and 34. The frame 56 is dependently suspended from the main frame 12 by four chains 58 at its corners. Additionally, two telescoping stabilizers 60 pivotally connected at their upper and lower ends to the frames 12 and 56, respectively, serve to stabilize the frame 56.

The rectangular frame 56 carries a depending peripheral skirt 62 which engages the pavement, during operation of the machine 10, and which cooperates with the frame to provide a shroud means encompassing the rotary surfacing means 18, the sprayers 30, and the vacuum heads 32 and 34 to assist in confining the water. The water is further confined by an inner shroud means 64, FIG. 2, substantially completely enclosing the rotary surfacing means 18 and the sprayers 30.

In the particular embodiment of the invention illustrated in the drawings, the machine has associated therewith a trailer 70 and a tank truck 72, the trailer 70 being connected to the rear end of the main frame 12 of the machine 10 by a transverse pivot means 74. The tank truck 72 is shown as a separate, independent unit.

The trailer 70 carries a vacuum pump or blower 76 the intake side of which is connected, by lines 78, to the upper end of a cyclone separator 80 on the trailer. The separator 80 is provided below its upper end with tangential inlets 82 connected by lines 84 to the ends of the transverse tubular member 48 of the yoke 46 forming part of the vacuum means 44.

With the foregoing construction, the air drawn into the vacuum heads 32 and 34, along with entrained water and cuttings produced by the rotary surfacing means 18, enter the separator tangentially and tend to fall toward the lower end thereof, as indicated in FIG. 3. The air is drawn out through the lines 78 by the vacuum pump 76, an intervening filter 86 minimizing the drawing off of water and solid particles. The exhaust side of the vacuum pump 76 has connected thereto an exhaust line 88 which discharges at any suitable point, such as downwardly against the pavement under the trailer 70.

The trailer 70 also carries a pump 90 the intake side of which is connected to the lower end of the separator 80 by a line 92. Thus, the pump 90 continuously draws water and solids from the lower end of the separator 80, these being delivered, through a hose 94, to the first of a series of settling tanks 96, 98 and 100 carried by the tank truck 72. The second settling tank 98 is separated from the first by a weir 102 surmounted by a screen 104, and the third settling tank 100 is separated from the second by a weir 106 surmounted by a filter 108. With this construction, recovered water flowing through the series of settling tanks 96, 98 and 100 is at least reasonably clear and free from solid particles when it reaches the third tank 100.

The water in the tank 100 is reused for the purpose of cooling the rotary saws 28, and for laying dust produced thereby. To achieve this, the water from the tank 100 is returned to the sprayers 30 by a pump 110 on the truck 72 and connected to the sprayers by a hose 112. Preferably, the hoses 94 and 112 are of substantial length so that the truck 72 does not need to move in unison with the machine 10 and its trailer 70. If desired, the hoses 94 and 112 may be long enough that the truck 72 needs be moved only occasionally.

It will be understood that the water recovered and reused in the foregoing manner must be supplemented by makeup water to offset that which cannot be recovered. However, the percentage of makeup water is quite small since virtually all of the water can be recovered, given a vacuum pump 76 of sufficient capacity.

Although an exemplary embodiment of the invention has been disclosed for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment.

Claims

I claim as my invention:

1. In a pavement surfacing machine the combination of:

a. frame means having longitudinally spaced front and rear ends;

b. front wheel means connected to and supporting said frame means adjacent said front end thereof;

c. rear wheel means connected to and supporting said frame means adjacent said rear end thereof;

d. power means carried by said frame means;

e. propelling means connecting said power means to one of said wheel means for propelling the machine;

f. transversely extending rotary surfacing means carried by said frame means between said front and rear wheel means, and rotatable about a transverse axis, for cutting grooves in pavement over which the machine runs, in the direction of movement of the machine;

g. means connecting said power means to said rotary surfacing means for driving said rotary surfacing means;

h. means for delivering water to a transversely extending zone of engagement between said rotary surfacing means and the pavement;

i. transversely extending, downwardly facing vacuum head means paralleling said rotary surfacing means, and spaced longitudinally from said rotary surfacing means in the direction of longitudinal movement of said rotary surfacing means through said zone of engagement, whereby said rotary surfacing means propels water toward said vacuum head means;

j. vacuum means connected to said vacuum head means for causing the latter to pick up water and cuttings there adjacent;

k. another transversely extending, downwardly facing vacuum head means paralleling said rotary surfacing means on the opposite side thereof from the vacuum head means first mentioned, and also connected to said vacuum means;

l. shroud means surrounding said rotary surfacing means and said vacuum head means and having depending skirt means engageable with the pavement; and

m. flexible means dependently suspending said vacuum means so that they may float relative to said rotary surfacing means.