Abstract:
A stud finder in one embodiment includes a first surface configured to be positioned adjacent to an object, a second surface generally opposite the first surface, an orifice opening to the first surface and to the second surface, a stud sensor configured to sense a structure through the object, and a vacuum source configured to draw a first vacuum in the orifice.

Description:
This application claims the benefit of U.S. Provisional Application No. 61/746,318, filed Dec. 27, 2012, the entire contents of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure relates to devices for detecting structures through other objects. 
     BACKGROUND 
     In general, there are known devices used for detecting lines, pipes, metal beams, or wooden beams or studs in walls, ceilings, and floors. These devices are referred to herein as “stud finders”. Stud finders are particularly useful in the field of interior finishing work in which the locations of wooden studs behind a covering surface, such as drywall, are concealed after the covering surface is installed. For instance, when hanging an object on a wall, it is advantageous to fasten a hanger for the object onto a stud behind the covering surface. The increased vertical load bearing capability of a wall hanger attached to a stud is highly desirable compared to the load bearing capability of a wall hanger attached to a wall anchor in the covering surface or only to the covering surface itself. 
     When a stud is located behind the covering surface, the position of the stud is frequently marked so that a hole can be drilled into the covering surface and the stud. Significant dust and other debris are generated when the covering surface, particularly drywall or plasterboard, is removed during the drilling operation. This accumulation of dust and other debris is often unwanted because of the tedious cleanup associated with removing drill debris from finished interior spaces. Therefore, improvements to devices for interior finishing work that enable a single device to locate objects enclosed in or behind media and collect portions of the media when the media is removed to expose the objects are desirable. 
     SUMMARY 
     A stud finder in one embodiment includes a first surface configured to be positioned adjacent to an object, a second surface generally opposite the first surface, an orifice opening to the first surface and to the second surface, a stud sensor configured to sense a structure through the object, and a vacuum source configured to draw a first vacuum in the orifice. 
     A method of working an object includes positioning a stud finder proximate to the object, activating a sensor of the stud finder, moving the device across the object, sensing a structure through the object, drawing a vacuum in an orifice in the stud finder with the stud finder, inserting a tool through the orifice, and working the object with the tool. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a left-perspective view of a stud finder including a vacuum source and a tool orifice; 
         FIG. 2  is a front plan view of the stud finder of  FIG. 1 ; 
         FIG. 3  is a right plan view of the stud finder of  FIG. 1  showing respective heights of a vacuum seal and a rear seal in relation to a lower housing of the stud finder; 
         FIG. 4  is a back plan view of the stud finder of  FIG. 1 ; 
         FIG. 5  is a left plan view of the stud finder of  FIG. 1 ; 
         FIG. 6  is a right-perspective view of the stud finder of  FIG. 1 ; 
         FIG. 7  is a bottom-perspective view of a stud finder incorporating a first embodiment of a vacuum seal protector configured to protect the vacuum seal as the stud finder is moved across a surface; 
         FIG. 8  is section view through two slider pads of the vacuum seal protector of  FIG. 7 ; 
         FIG. 9  is a bottom-perspective view of a stud finder incorporating a second embodiment of a vacuum seal protector; and 
         FIG. 10  is a flow diagram of a method for operating the stud finder of  FIG. 1  to detect a structure through an object and to work the object. 
     
    
    
     DETAILED DESCRIPTION 
     For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the disclosure is thereby intended. It is further understood that the disclosure includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the disclosure as would normally occur to one skilled in the art to which this disclosure pertains. 
       FIGS. 1-6  show a stud finder  10  configured to detect a structure through an object. In the embodiment shown, the stud finder  10  is a combination device which includes a dust collector that is operable to collect dust and other debris generated when an object is worked, such as by drilling with a power tool. 
     The stud finder  10  has a housing  22  formed from a lower half shell  24  and at least one upper half shell  26 . The lower  24  and upper  26  half shells are secured to each other by a plurality of fasteners  25  as best shown in  FIG. 4 . In other embodiments, the lower  24  and upper  26  half shells are attached by other desired fastening methods. For example, the half shells  24 ,  26  in some embodiments are configured with respective features that enable the half shells  24 ,  26  to engage each other via a snap fit. In further embodiments, the half shells  24 ,  26  are ultrasonically welded to each other. 
     A removable debris cover  28  engages the housing  22  and forms an enclosed debris container for containing dust and other debris. The debris cover  28  in some embodiments independently forms the volume for containing the debris and is configured to be disengaged from the housing  22  for disposal of the collected debris. In other embodiments, the debris cover  28  forms the volume in cooperation with one or more of the lower half shell  24  and the at least one upper half shell  26 . In these other embodiments, the debris cover  28  is opened or removed from the housing  22  and the collected debris is emptied from the stud finder  10 . 
     The debris cover  28  as shown is formed from a transparent colored material, but other material colorings are possible. The transparency of the debris cover  28  enables a user operating the device  10  to determine a quantity of the dust and other debris collected. In some embodiments, such as those utilizing non-transparent colored materials for the debris cover  28 , the device  10  includes alternative features for the user to determine the quantity of dust and other debris collected. For example, an access hole (not shown) is formed in an appropriate location on the debris cover  28  or the housing  22  in some embodiments so that the quantity of dust and other debris contained in the debris container can be visually perceived. 
     In further embodiments, a sensor or a transducer is disposed or integrated in the debris cover  28  to monitor and determine the presence of the debris. A notification system with an audible feature or a light feature is configured to alert a user of the need to remove of excessive debris contained in the debris container. If the level of the debris is higher or above a predetermined threshold, a signal from the sensor is sent to the notification system which in turn triggers the notification system to produce audible energy or light energy. The notification system may be either electrically coupled to the sensor as two separate components or mechanically integrated into a housing for encapsulating the sensor as a single sensor package system. The sensor may be for example, a MEMS sensor, capacitive sensor, a resistive sensor, a volume sensor, a debris sensor, or other sensing device. 
     An orifice  27  extends completely through the stud finder  10  and opens to the housing  22  at a front mouth  29 . The orifice  27  opens to the outer surface of the debris cover  28  at a rear mouth  31 . The orifice  27  is configured to permit a portion of a tool, such as a drill bit, to pass through the orifice  27 . In some embodiments, the front mouth  29  has an orifice protector  33 , such as a metal disk or washer, fastened to or press fit into the debris cover  28 . The orifice protector  33  functions to protect the debris cover  28  from gouging or excessive abrasion from tools which are too large or not concentrically aligned with the orifice  27  prior to insertion of the drill bit through the orifice  27 . 
     A tool cleaner  35  is disposed between the front  29  and rear  31  mouths to clean the various surfaces of, for example, a drill bit after the bit has been used to work an object. The tool cleaner  35  forms a tool cleaner orifice  39  through which the drill bit passes to engage the object. The tool cleaner  35  is configured to surround and physically interact with the various surfaces of tools including drill bits such that any dust or debris on the surface of the tool is removed as the tool is moved through the orifice  27 . In some embodiments, the tool cleaner  35  is an elastomeric material that substantially extends across the entire orifice  27 , but that permits a tool to pass through it. In other embodiments, the tool cleaner  35  includes a plurality of bristle-like elements arranged to surround and physically interact with the various surfaces of the tool. 
     A vacuum seal  37  is attached to an external surface of the lower half shell  24  to enable the stud finder  10  to be affixed to an object when the dust collection function of the stud finder  10  is used. The vacuum seal  37  forms a closed boundary having a surface that is offset from the external surface of the lower half shell  24 . When the stud finder  10  is held adjacent to the object, a pump (not shown) disposed within the housing  22  is configured to generate a vacuum within a vacuum space defined by the covering surface, the vacuum seal  37 , and the lower half shell  24 . The pump draws air from the vacuum space through a vacuum orifice  38  formed in the lower half shell  24  and located within the boundary formed by the vacuum seal  37 . 
     In addition to generating the vacuum within the vacuum space, the pump is further configured to generate a vacuum within the debris container. This negative pressure causes air to be drawn through the front and rear mouths  29 / 31 , thereby facilitating the capture and containment of dust and other debris when the covering surface is drilled. A rear seal  40  is secured to the lower half shell  24  and is positioned concentric to the rear orifice  31 . The rear seal  40  forms a rear seal orifice  41  that enables the rear seal  40  to be positioned around the portion of the object worked by the tool. The positioning of the rear seal  40  over the drilled portion of the object ensures substantially all of the dust and other debris from the object is collected by the stud finder  10 . The rear seal  40 , in a form of a gasket, is made from material having polymer properties, such as rubber or plastic material. The real seal  40  firmly compresses to the wall during operation. 
     The vacuum seal  37  is formed from a foam or elastomeric material that provides sufficient flexibility to enable the vacuum seal  37  to conform to surface imperfections on the covering surface and to maintain a substantially air-tight seal therebetween. The vacuum seal  37  has a height relative to the external surface that allows the vacuum seal  37  to compress during vacuum formation, but that ensures sufficient clearance between the stud finder  10  and the object. Additionally, the rear seal  40  provides a positive stop for the lower half shell  24  as the pump-generated vacuum in the vacuum space draws the stud finder  10  closer to the object and compresses the vacuum seal  37 . 
     At least one sensor, for example, a capacitive sensor having at least one capacitor plate  30 , is positioned within the housing  22  and is configured to generate an electrical field. Also positioned within the housing are an electronics system (not shown) for signal production and evaluation and an energy supply system (not shown), for example, batteries or accumulators. As the electrical field generated by the capacitive sensor is passed over the object, an incongruity in or beneath the object, such as a wooden stud, causes a change in the dielectric constant of the object. This change in the dielectric constant of the object is detectable by the electronics system, enabling the system to indicate the presence of a stud behind the object via a location signal. 
     Other types of sensors are employed to locate structures enclosed in or behind the object in other embodiments. For example, the stud finder  10  in some embodiments includes an inductive sensor having a coil system configured to locate metal structures enclosed by or located beneath an object. Inductive devices produce a magnetic field that is disturbed by the enclosed metallic structure. The magnetic field modified in this manner is measured by a detector having one or more coils, so that the position of the enclosed metallic structure can be located by shifting or moving the stud finder  10  over the object covering or enclosing the structure. In other embodiments, the stud finder  10  includes a Hall Effect stud sensor configured to detect the presence of a ferrous material. Other sensors such as GMR sensors, metal sensors are suitable for the stud finder  10 . 
     The stud finder  10  further includes a display  32  for transmitting an output signal correlated with the location signal produced by the electronics system. Through the display  32 , it is possible to visually represent the strength of the location signal as the stud finder  10  is moved over the object and encounters studs or other structures. For instance, the display  32  in some embodiments includes a plurality of aligned LEDs  34  or similar light emitting devices that are selectively triggered as the stud finder  10  is moved toward or away from the location of the stud behind the object. Similarly, the display  32  in other embodiments comprises a segmented bar graph display or a graphic LCD display to represent the strength of the location signal. 
     The stud finder  10  in some embodiments includes an audio device (not shown) that generates audible sounds that represent the strength of the location signal. For example, the audio device generates a series of discrete tones or beeps that increases or decreases in frequency as the stud finder  10  approaches or moves away from the stud. The audio device is used alone or in conjunction with the display  32  to represent the strength of the location signal produced by the electronics system. 
     The stud finder  10  includes a number of operating elements configured to control the stud locating and dust collecting functions of the stud finder  10 . A scanning button  36  provides power to the electronics system and the at least one sensor to activate the stud locating function of the stud finder  10 . A pump switch  42  configured to toggle between an ON position and an OFF position provides power to the pump when the switch is toggled to the ON position. In some embodiments, the pump switch  42  is a touch control switch, a pressure sensing switch, a projected capacitive switch, or other smart sensing switch configured to actuate the stud finder  10 . 
     The stud finder  10  further includes a vacuum release button  44  that actuates a release valve (not shown) cooperating with a vacuum release orifice  46  formed in the lower half shell  24 . The vacuum release orifice  46  provides a path for air to return to the vacuum space to equalize the pressure differential between the vacuum space and the air outside the vacuum space. Equalization of the pressure between the vacuum space and the air outside vacuum space enables the stud finder  10  to be removed from the covering surface. 
       FIGS. 7-9  show respective first  16  and second  18  embodiments of a vacuum seal protector incorporated on respective stud finders  12  and  14 . In the first embodiment shown in  FIGS. 7 and 8 , the vacuum seal protector  16  includes a plurality of slider pads  48  spaced along the external surface of the lower half shell  24 . As best shown in  FIG. 8 , the slider pads  48  are slidably disposed within respective recesses  50  formed in the lower half shell  24 . A first resilient member  52 , such as a compression spring, biases the slider pads  48  away from the external surface of the lower half shell  24 . The biased slider pads  48  ensure there is a clearance between the covering surface and the vacuum seal  37  when the stud finder  12  is moved across a surface. The slider pads  48  are positioned over the lower half shell  24  in such a way that the lower half shell  24  remains essentially parallel with the surface of an object as the stud finder  12  is moved to engage the vacuum seal  37  with the covering surface. 
     The slider pads  48  have a sliding surface that interacts with the covering surface as the stud finder  12  is moved over the surface. As shown in  FIGS. 7 and 8 , the sliding surface is flat, or, in other words, the sliding surface is essentially parallel with the external surface of the lower half shell  24 . The sliding surface in other embodiments is a contoured surface, such as a pointed or conical surface or a hemispherical surface. To accommodate interaction of the stud finder  12  with different types of covering surfaces, the stud finder  12  is provided with multiple sets of slider pads  48  with each respective set having respective sliding surfaces that are different from one another. 
     In the second embodiment shown in  FIG. 9 , the vacuum seal protector  18  includes at least two slider plates  54  positioned at opposing ends of the lower half shell  24 . The slider plates  54  are affixed to respective second resilient members  56 , such as foam or sponges, that are attached to the lower half shell  24  and bias the slider plates  54  away from the external surface of the lower half shell  24 . The biased slider plates  54  ensure there is a clearance between the covering surface and the vacuum seal  37  when the stud finder  14  is moved across the covering surface. 
     The second resilient members  56  are formed from a foam or elastomeric material that provides sufficient flexibility and that resists permanent deformation or set. In some embodiments, the vacuum seal  37  and the second resilient members  56  can be formed from the same material. The second resilient members  56  have a height that is approximately the same as the height of the vacuum seal  37 . In some embodiments, however, the second resilient members  56  have a height that is more or less than the height of the vacuum seal  37  as long as the slider plates  54  have a corresponding thickness sufficient to protect the vacuum seal  37  from abrasion during movement over the covering surface. In the embodiment shown in  FIG. 9 , the second resilient members  56  have the same height as the vacuum seal  37  and the slider plates  54  have a thickness of approximately 2 mm. 
     In other embodiments, the stud finder  10  is adapted to perform additional functions related to interior finishing work. For example, the electronics system of the stud finder  10  can be further configured to operate a line generator to illuminate a linear path along the covering surface. The illuminated path can be used, for example, to identify multiple, spaced apart positions along the covering surface to be drilled. In other embodiments, the electronics system of the stud finder  10  is further configured operate a leveling mechanism in conjunction with the line generator to illuminate a linear path along the covering surface that is “level” in relation to the force of gravity. 
     A flow diagram of a method  100  for operating a stud finder is shown in  FIG. 10 . The method  100  is described with reference to the stud finder  10  shown in  FIGS. 1-6 . A user implements the method  100  by first holding the stud finder  10  against the surface of an object behind which at least one stud or other structure is located and activating the stud locating function of the stud finder  10  (block  102 ). The user activates the stud locating function by pressing and holding the outwardly biased scanning button  36 . While the stud locating function is activated (block  102 ), the user moves the stud finder  10  across the surface of the object to locate stud positions (block  104 ). 
     The display  32  changes as the stud finder  10  approaches a stud enclosed behind the surface of the object. For example, one or more selected LEDs of the plurality of aligned LEDs are triggered as an edge of the stud is approached by a center of the stud finder  10 . A central LED is triggered in some embodiments when the edge of the stud coincides with the center of the stud finder. The user identifies the location of the stud by observing the display  32  as the stud finder is moved across the surface of the object. 
     The studs in some embodiments are located by marking at least two opposing edge positions of the stud on the covering surface. In other embodiments, the stud finder  10  has a sensor configuration that enables the stud finder to simultaneously identify the opposing edges and the center of the stud. A notch  58  formed in the lower half shell  24  is positioned to coincide with the center of the stud finder  10 . The notch  58  facilitates the user in marking the at least two opposing edge positions or the center position of the stud. When a stud is located by the stud finder  10 , the user determines if one or more drilling positions need to be marked on the covering surface to facilitate drilling into the located stud (block  105 ). If position marking is needed, the user marks the one or more drilling positions on the surface of the object based on the locations of the studs (block  106 ). In some embodiments, the user estimates the drilling position based on the detected location of the stud and does not physically mark the drilling position on the covering surface. The scanning button  36  is released when there are no more studs to be located. 
     To use the dust collecting function of the stud finder  10 , the user aligns the orifice  27  of the stud finder  10  with the marked or determined position to be drilled (block  108 ). With the stud finder  10  on the surface of the object, the pump switch  42  is toggled to the ON position to provide power to the pump (block  110 ). In the embodiments incorporating a vacuum seal protector ( FIGS. 7-9 ), the user applies enough force on the device to overcome the resilient bias of the vacuum seal protector to seat the vacuum seal  37  against the covering surface. The pump generates a vacuum in the vacuum space that is strong enough to hold the stud finder  10  against the covering surface without assistance from the user. Simultaneously, the pump generates a negative pressure within the debris container that draws air into the debris container via the orifice  27 . The seal  40  about the rear mouth  31  prevents air from passing into the orifice  27 . Accordingly, once the vacuum is operating, air continues to be sucked into the debris container primarily via the front mouth  29 . 
     While the pump is operating (block  110 ), the user passes the tool through the front  29  and rear  31  mouths and drills into the surface of the object and, if desired, into the stud (block  112 ). Any dust or debris generated from the drilling is captured by the stud finder  10  due to the positioning of seal  40  about the area being worked and the vacuum being drawn on the orifice  27  through the debris container. Moreover, movement of the drilling tool through the tool cleaner  35  positioned between the front  29  and rear  31  orifices removes any dust or debris attached to the surfaces of the tool as air is being sucked into the orifice  27  through the front mouth  29 . 
     Once the marked position is drilled or otherwise worked (block  112 ), the user determines if there are more marked positions to be drilled (block  114 ). If there are additional marked positions to be drilled, the user presses the vacuum release button  44  to release the stud finder  10  from the object (block  116 ) and blocks  108 - 112  are repeated. The vacuum release button  44  enables the user to remove the stud finder  10  from the object while the pump is operating. To reposition the stud finder  10  with the pump operating, the user continues to press the vacuum release button  44  until the stud finder  10  is properly positioned for drilling the next marked position. 
     If there are no additional marked positions to be drilled, the user toggles the pump switch  42  to the OFF position and removes the stud finder  10  from the covering surface ( 118 ). If a residual vacuum remains after the pump is deactivated, the user can press the vacuum release button  44  to release the stud finder  10 . The user can empty the debris container at any time if the dust or other debris collected in the container needs to be removed. To empty the debris container, the debris cover  28  is disengaged from the housing  22  and either the debris cover  28  itself is removed and emptied or, in some embodiments, the debris cover  28  is opened and the dust or other debris is emptied from the housing  22 . 
     While the disclosure has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the disclosure are desired to be protected.