Abstract:
An improved portable locator is described which is configured for locating relative to a position beneath the surface of the ground. The improvement includes a marking arrangement for marking the surface of the ground. In one aspect, the portable locator is configured having a marking arrangement which utilizes a replaceable aerosol paint canister. Spray of paint from the canister may be initiated, for example, electrically or using a suitable mechanical actuation linkage. In another aspect, an operator of the portable locator is able to mark the surface of the ground using the portable locator and while holding the portable locator in generally the same position and/or stance as the locator is used for locating purposes.

Description:
This is a continuation application of copending prior Application No. 09/539,899, filed on Mar. 30, 2000, the disclosure of which are incorporated herein by reference. 
    
    
     The present invention relates generally to in-ground locating using a portable locator and, more particularly, to a able locator including an integral ground marking arrangement. 
     Portable locators have become popular, for example, as part of locating arrangements used with underground horizontal boring equipment. In particular, hand held portable locators enable tracking of a boring tool which is configured for emitting a locating field from the position of the boring tool beneath the surface of the ground. As examples of state of the art locating systems which incorporate portable walk over locators see U.S. Patent No. 4,387,380 entitled APPARATUS FOR DETERMINING THE DISTANCE TO A CONCEALED OBJECT WHICH IS RADIATING AN ALTERNATING CURRENT SIGNAL (hereinafter the &#39;380 patent) and U.S. Patent No. 5,633,589 entitled DEVICE AND METHOD FOR LOCATING AN INGROUND OBJECT AND A HOUSING FORMING PART OF SAID DEVICE (hereinafter the &#39;589 patent). It is noted that the latter patent is commonly assigned with the present application. 
     The &#39;589 patent utilizes a hand held portable locator which can be held at a user determined height above the surface of the ground. Because the height of the locator above the surface of the ground has a critical effect on locating measurements, an ultrasonic detecting arrangement within the locator senses the distance between the surface and the portable locator during measurements of the locating field. 
     The portable locator of the &#39;340 patent, in contrast, utilizes a stand-off leg for establishing locator height. When locating field measurements are taken, the lower end of the stand-off leg is positioned on the surface of the ground so as to fix the height of the measurement point within the locator at a predetermined distance above the surface of the ground. 
     In the normal course of a horizontal drilling operation, using either of the aforedescribed portable locator styles, it is often desired to mark the surface of the ground directly above the underground path of the boring tool or to make other reference marks. To that end, the operator of the portable locator will often carry some sort of marking device such as a canister of aerosol paint. Aerosol paint canisters are readily available in various configurations for marking the surface of the ground. Moreover, extension handles are also available and are popular for holding one of these aerosol canisters, the combination of which may be referred to hereinafter as a marking wand. Using a marking wand, the operator can mark the surface of the ground from a substantially upright position. An operator can determine a location on the surface of the ground using the locator in one hand and then swing the portable locator out of the way to mark the surface of the ground with paint by having the marking wand in the other hand. While this arrangement seems generally convenient, it is unfortunate that still further tasks are normally required of the locator operator, as will be described immediately hereinafter. 
     In addition to operating the portable locator while marking the surface of the ground, the locator operator is normally required to communicate guidance commands to another operator stationed at a drill rig powering the underground boring tool. This communication, in most instances, is performed using walkie-talkies. With the portable locator in one hand and the marking wand in the other, the portable locator operator must typically place either the marking wand or the locator on the ground in order to free one hand for operating the walkie-talkie. In this regard, it should be appreciated that the aerosol marking wand and portable locator are each somewhat bulky and inconvenient to repeatedly place on the ground and pick up. Moreover, there may be situations in which the portable locator itself requires two hands to operate or the operator requires a free hand for additional tasks such as, for example, recording log entries or using a walkie-talkie to issue drilling commands. For these and other reasons, portable locator operators are seen to encounter problems in having an insufficient number of hands to operate three or more separate devices, all of which are important to the drilling operation. 
     The present invention provides a portable locator having an integral ground marking arrangement which serves to reduce or eliminate the foregoing problems in a highly advantageous and heretofore unseen way. 
     SUMMARY OF THE INVENTION 
     As will be described in more detail hereinafter, there is disclosed herein an improvement in a portable locator configured for locating relative to a position beneath the surface of the ground. The improvement being a marking arrangement for marking the surface of the ground. 
     In one aspect of the invention the portable locator is configured having a marking arrangement which utilizes a replaceable aerosol paint canister. Spray of paint from the canister may be initiated, for example, electrically or using a suitable mechanical actuation linkage. 
     In another aspect of the invention, an operator of the portable locator of the present invention is able to mark the surface of the ground using the portable locator and while holding the portable locator in generally the same position and/or stance as the locator is used for locating purposes. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention may be understood by reference to the following detailed description taken in conjunction with the drawings briefly described below. 
     FIG. 1 is a diagrammatic cross-sectional view, in elevation of a first embodiment of a portable locator configured for inground locating shown here to illustrate a marking arrangement which forms part of the portable locator in accordance with the present invention. 
     FIG. 2 is a partial, enlarged cross-sectional diagrammatic view of the first embodiment of the portable locator of FIG. 1, shown here to illustrate details of the ground marking arrangement of the present invention which forms a portion of a stand-off leg. 
     FIG. 3 is diagrammatic cross-sectional view, in elevation of a second embodiment of a portable locator configured for inground locating shown here to illustrate an alternative ground marking arrangement which forms part of the portable locator in accordance with the present invention. 
     FIG. 4 is a partial, enlarged cross-sectional diagrammatic view of second embodiment of the portable locator of FIG. 3, shown here to illustrate details of the alternative ground marking arrangement of the present invention which forms a portion of the stand-off leg of the portable locator. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning to the drawings, wherein like components are designated by like reference numerals throughout the various figures, attention is initially directed to FIG.  1 . This figure illustrates a first embodiment of a portable hand held locator manufactured in accordance with the present invention and generally indicated by reference numeral  10 . It should be appreciated that portable locator  10  is suitable for use as part of virtually any underground locating system in which a portable locator is useful. Therefore, the described configuration may be modified in any manner that is suited to a particular application. In the illustrated configuration, portable locator  10  includes a housing  12  which encloses an electronics package  14  supported by a plurality of mounts  16 . A cabling assembly  18 , which is only partially shown for purposes of clarity, is used to interconnect the electronics package with other portions of the locator. An “X” configured antenna assembly  20  is located in housing  12  below electronics package  14 . 
     Still referring to FIG. 1, a handle assembly  22  includes a hand grip portion  24  by which an operator (not shown) normally carries the locator during use. A push button switch  25  is mounted in the hand grip for ease of actuation by the operator and is electrically connected (not shown) to electronics package  14 . The push button switch may be actuated, for example, when a locating measurement is taken or in performing other tasks, as will be described. A battery compartment portion  26  of the handle assembly, in this instance, is configured to hold three standard C cell batteries  28  for powering the overall unit. The housing is cut away to provide a battery access opening  30 . A display assembly  32  is provided for conveying information relating to the locating operation in any suitable display format. A stand-off leg  34  is attached to housing  12  using a hinge  36 . During operation, the locator is configured as illustrated with stand-off leg  34  extending downwardly. During storage or transport of locator  10 , stand-off leg may be folded (not shown) against housing  14  using hinge  36  so as to result in a more compact configuration. As described above, stand-off leg  34  includes a predetermined length which establishes the distance of antenna assembly  20  above the surface of the ground when a lowermost end  38  of the stand-off leg is placed into contact with a surface  40  of the ground during locating measurements. 
     Referring to FIG. 2 in conjunction with FIG. 1, in accordance with the present invention, the lower end of stand-off leg  34  is configured for receiving an aerosol paint canister  42  within a paint chamber  44  defined by the stand-off such that a spray nozzle  46  of the canister is directed downwardly and supported at a suitable, predetermined distance above the surface of the ground when the lowermost end contacts the surface of the ground. When canister  42  is fully received in the paint chamber, FIG. 2 best illustrates an upper edge  48  of a support ring  50  contacting a peripheral edge in the outline of the aerosol canister. Paint chamber  44  may be sized such that the nozzle end of aerosol canister  42  is first positioned in the paint chamber at least partially seated against upper edge  48  of the support ring. Thereafter, the upper end of the canister, as illustrated in FIG. 1, may be “snapped” into position against a holding face  52  by moving the upper end of the canister in a direction indicated by an arrow  54  such that the aerosol canister is captured between support ring  50  and holding face  52 . While the illustrated arrangement is well suited for supporting the aerosol canister, it is to be understood that the present invention contemplates the use of any arrangement which removably supports canister  42  at the desired position within the stand-off leg. Moreover, aerosol canisters are available in many configurations and appropriate modifications or adapter fittings may be provided to accommodate these various configurations either existing or to be developed. 
     Referring to FIG. 2, a gusset  56  pivotally supports a spray lever  60  having an pedal end  62  and a nozzle actuation end  64 . In order to mark the surface of the ground, the operator first places lowermost end  38  onto the surface, as shown. Spray lever  60  is configured such that downward force applied to pedal end  62  by the foot  66  (only partially shown) of the operator causes nozzle actuation end  64  of the spray lever to move upwardly, thereby engaging nozzle  46  and causing a spray  68  of paint to be emitted downwardly onto the surface of the ground. It should be appreciated that spray lever  60  may be configured in any appropriate manner, for example, based on the specific design of nozzle  46 . 
     Referring now to FIG.  3  and having described a first embodiment of the locator of the present invention, it should be appreciated that a wide range of other embodiments is also possible. For example, FIG. 3 illustrates a second embodiment of the portable locator of the present invention generally indicated by the reference number  100 . It should be appreciated that a majority of the components shown in FIG. 3 have been described previously, therefore descriptions of these components will not be repeated for purposes of brevity. 
     Referring to FIGS. 3 and 4, in accordance with the present invention, locator  100  includes an electrical actuation arrangement indicated by the reference number  102  for initiating marking of surface  40  of the ground. As best seen in FIG. 4, electrical actuation arrangement  102  includes an extended lever  104  pivotally attached at one end to gusset  56  and attached at an opposing end to a plunger  106  of a solenoid  108 . The extended lever may be slidably secured onto plunger  106 , for example, by a one-way lock washer  110 . Solenoid  108  is connected to electronics package  14  in a suitable manner which is not shown since such it is considered that such interconnections may readily be provided by one having ordinary skill in the art. Electrical power may be routed between housing  12  and stand-off leg  34 , for example, using a slip ring arrangement in hinge  36 . 
     Still referring to FIGS. 3 and 4, electronics package  14  may be configured to respond to a predetermined actuation of switch  25  to initiate the marking process. For example, if switch  25  is depressed twice in rapid succession and held closed the electronics package may respond by actuating solenoid  108 . In this regard, the electronics package includes a driver circuit which, in one implementation, serves to form a series connection of batteries  28  and solenoid  108  in response to the predetermined actuation of switch  25 . Thereafter, when electrical current flows through solenoid  108  plunger  106  moves upward to move the free end of extended lever  104  upward so as to apply force to spray nozzle  46  causing paint  68  to spray onto surface  40  of the ground. It is noted that the depicted arrangement can be used to mark the surface of the ground irrespective of whether the lowermost end of stand-off leg  34  is in contact with the surface of the ground. It is to be understood that alternative electrical actuation arrangements (not shown) may be configured in many other ways with respect to either mechanical or electrical aspects within the scope of the present invention. For example, a solenoid may apply a lateral force to spray nozzle  46 . Of course, electrical actuation arrangements may be configured to suit particular configurations of aerosol paint canisters. As another example, a switch (not shown) separate from switch  25  may be provided in a position on the locator convenient to the operator to initiate marking of the surface of the ground. 
     Referring to FIG. 1, the present invention also contemplates a completely mechanical actuation arrangement (not shown) incorporating a trigger in handle assembly  22  for causing paint to spray from canister  42 . The provision of such a mechanical linkage is considered to be within the ability of one having ordinary skill in the art in view of this overall disclosure. 
     Referring to FIGS. 1-4, having described several implementations of the ground marking locator arrangement of the present invention, it is now appropriate to discuss its advantages. It should first be appreciated that an operator of the locator of the present invention is able to mark the ground without the need to carry a separate marking device. In the instance of locator  10 , the operator simply depresses pedal end  62  of spray lever  60  while, in the instance of locator  100 , the operator simply actuates switch  25  in a predetermined way. In either case, a mark is formed on the ground while the operator&#39;s other hand remains free to perform other tasks such as, for example, operating a walkie-talkie. At the same time, it should be appreciated that, when using either implementation, the operator may remain standing in a substantially upright position without the need to repeatedly bend over in order to mark the ground. In other words, the operator is able to mark the ground while holding the locator in substantially the same manner as the locator is held for locating purposes. For these reasons alone, the present invention is submitted to be highly advantageous. The ground marking portable locator of the present invention has not been seen heretofore by Applicants and is thought to be a significant enhancement in the field. As one example, in systems using a portable locator for tracking the underground progress of a boring tool, an operator may efficiently mark the path of the boring tool on the ground surface without the need frequently change body positions and while one hand remains free to attend to other tasks. 
     It should be appreciated that the present invention contemplates marking the surface of the ground using materials other than aerosol paint which have not been shown for purposes of brevity. For example, chalk may be used which is dropped onto the ground surface. As another example using chalk, a chalk stick may be removably mounted at the lowermost end of stand-off leg  34 . As still another example, a pin which support a marking flag or tuft may be pressed or injected into the ground. 
     It should be noted that the present invention is not limited to the embodiments and methods described herein. For instance, the marking arrangement of the present invention may be used to identify the underground location of a utility. Such underground utilities may be located using a signal induced thereon or in some other suitable manner. Any arrangement or method useful in a portable locator for marking the surface of the ground is considered to be within the scope of the present invention. Therefore, the present examples are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims.