Device For Extracting Previously Driven Probe Elements From A Solid Structure

Abstract

A hand operated tool for extracting the base unit for a receptacle device of the type having probe elements which have previously been driven firmly into a laminated electrical distribution structure. The tool comprises a base that surrounds the base unit, a frame attached to the base that supports a movable extraction plate and a locking means that secures the plate to the base unit to be extracted. An actuating mechanism operated by a hand lever is connected to the extraction plate so that a steady, non-slipping lifting force can be applied on the base unit. Plunger means mounted on the tool frame extend downwardly into the upper ends of the probe elements and force them to expel a viscous fluid from their lower ends as the base unit and probe elements are raised and withdrawn from a laminated structure.

Description

This invention relates to a tool for extracting or removing elongated elements from a structure into which they were previously driven, and more particularly it relates to a tool for simultaneously extracting from a laminated floor structure a plurality of probe elements supported on the base unit of a receptacle device for an area type power and/or signal distribution system.

BACKGROUND OF THE INVENTION

In an area type power and signal distribution system a laminated structure having internal conductive layers is installed on a floor or wall area and electrical power and/or signal energy is supplied to the conductive layers from some external source. By installing a suitable receptacle device at any preselected location on the structure the power or signal energy can be extracted through probe elements of the receptacle device that have been driven into contact with the internal conductive layers. Such an area type system is shown in U.S. Pat. No. 3,809,966 and a receptacle device for the system is described in detail in U.S. Pat. No. 3,809,969. A major advantage of an area type distribution system is the capability of easily installing receptacle devices at any randomly selected location. Together with this is the requirement that such devices be also capable of being easily removed. Yet, in order for firm, lasting electrical contact to be accomplished between the probe elements of a receptacle device and the conductive layers, the elements are driven with considerable energy into structural media that provides a substantial gripping force. Thus, to extract the probe elements of a receptacle device in order to move it to another location a considerable force must be furnished to overcome the gripping force. Yet, it is essential that the probe elements be removed or extracted without damaging the laminated structure. Still further, it is essential that a tool for extracting the probe elements from a laminated structure be relatively easy and safe to operate by an average person of only ordinary or moderate strength. The present invention solves all of these problems.

Another problem which arose with the necessity to remove probe elements of a receptacle device previously installed was in providing a sealant to fill the hole left by the probe element as it was being extracted. As described in the aforesaid application covering a receptacle device, each of its probe elements may be provided with a cavity initially filled with a viscous sealant material. Thus, the problem here was to provide a means for dispensing this sealant from each probe element during the extraction process.

It is therefore a general object of the present invention to provide a tool for simultaneously extracting a plurality of previously driven probe elements from a laminated structure and moreover a tool which solves the aforesaid problems.

Another object of the present invention is to provide a tool for extracting probe elements as described that can be easily and safely operated by only a moderate amount of manual strength; that is durable and easy to maintain without the need for specialized labor or tools; and that is relatively economical to manufacture.

Yet another object of the invention is to provide a tool that will simultaneously extract a plurality of probe elements and also cause them to dispense a stored quantity of viscous sealant material.

SUMMARY OF THE INVENTION

A tool according to the invention has a stabilizing base plate adapted to rest on the floor surface to which is attached a frame that extends above an opening in the base plate. When in use the tool is positioned so that a base unit of a receptacle device is located within the opening of the tool base plate. A pair of locking members movably supported on the frame are positioned by a hand operated linkage to engage the receptacle base unit and secure it to an extraction plate. The latter is mounted on the lower end of an elongated actuator member having a rack of gear teeth along one side. The upper end of this actuator extends through a horizontal top guide plate on the frame and a clamping device mounted on this guide plate. The gear rack is engaged by meshing gear teeth of a rotatable circular gear that is journaled in a bearing assembly on the frame and attached to a lever arm extending from the side of the tool. Movement of the lever arm to rotate the gear causes a vertical movement of the actuator member, the extraction plate and hence the base unit secured to it. The relatively large mechanical advantage provided by the gear rack and lever produces an upward force that is sufficient to dislodge and extract all of the probe elements attached to the receptacle base unit when the lever is operated by any person with ordinary strength. Also supported by the frame of the tool are vertical plunger elements which are aligned with the upper ends of the probe elements being removed. These plunger elements are spring loaded and fit within the upper cavity portions of the probe elements so as to constantly exert an axial force sufficient to dispense a viscous sealant material from the lower end of each probe element as the extraction process takes place.

Another object of the present invention is to provide a tool having the aforesaid elements that function as described to extract a plurality of probe elements previously driven into a laminated structure.

Other objects, advantages and features of the present invention will become apparent from the following detailed description of one embodiment thereof, presented with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a view in perspective showing a portion of a laminated floor structure having a receptacle device mounted thereon;

FIG. 2 is a view in perspective similar to FIG. 1 showing the base unit of the receptacle unit;

FIG. 3 is a view in elevation showing an extraction tool embodying the principles of the present invention with the mechanism shown in position before extraction has occurred;

FIG. 4 is a view similar to FIG. 3 showing the tool after extraction of the base unit and probe elements has occurred;

FIG. 5 is a view in perspective showing a base unit of a receptacle device and portions of the extraction tool which engage the base unit;

FIG. 6 is an enlarged fragmentary view in elevation showing one end of the extraction tool;

FIG. 7 is an enlarged view in elevation and partially in section showing the extraction tool according to the present invention;

FIG. 8 is a view similar to FIG. 7 but of somewhat smaller scale showing the tool at the end of its extraction stroke with the probe elements removed;

FIG. 9 is an enlarged view in section taken along line 9--9 of FIG. 8;

FIG. 10 is a plan view of the tool taken along line 10--10 of FIG. 8 with portions broken away;

FIG. 11 is a bottom plan view taken along the line 11--11 of FIG. 8 with portions broken away;

FIG. 12A is an end view in elevation of the tool embodying the principles of the invention;

FIG. 12B is a fragmentary view in section taken along line 12B--12B of FIG. 12A;

FIG. 13 is an enlarged fragmentary view partially in section showing a plunger of the extraction tool in engagement with a probe element before the extraction cycle has commenced;

FIG. 14 is a view similar to FIG. 13 showing the probe element partially removed from a laminated structure as its sealant material is being expelled.

DETAILED DESCRIPTION OF EMBODIMENTS

With reference to the drawing, FIGS. 1 and 2 show portions of a laminated structure 20 for an area type power and/or signal distribution system. In the system shown for purposes of illustration, adjacent laminated panel sections spaced apart by channel members 22 are anchored to a basic floor surface. Suitable fasteners 24 extend downwardly into the channel members through tie-down strip members 26 that overlap the edges of the panel sections. A carpet layer 28 of some other suitable floor covering material is normally installed over the laminated structure. After its desired location has been determined, a receptacle device 30 is installed on the laminated structure as shown in FIG. 1. Such a receptacle device, as described in detail in the aforementioned U.S. Pat. No. 3,809,969 is comprised of a base unit 32 to which are attached a series of probe elements 34 that are driven into the laminated structure so as to make electrical contact with a pair of spaced apart internal conductive layers 36 and 38. Portions 40 extending below the body of the base unit (as shown in FIG. 3) contact a top conductive ground layer 42 of the structure. When the base unit is installed, the probe elements are driven by a substantial force into the laminated structure and, in order to make the necessary electrical contact, to a depth that provides a considerable gripping power on them. Thus, when it becomes necessary or desirable to move the receptacle device to some other location on the laminated structure, the probe elements must be withdrawn from the laminated structure, and this is accommplished by a tool 44 embodying the principles of the present invention.

In FIGs. 3 and 4, our tool 44 is shown in two operative positions. FIG. 3 shows it connected to a receptacle base unit ready to start the extraction cycle, and FIG. 4 shows the position of the tool elements at the completion of the extraction cycle with the receptacle base unit raised and the probe elements disengaged from the laminated structure.

In broad terms, the tool 44 comprises an elongated base plate 46 to which is attached an upwardly extending frame 48. At the upper end of the frame is a cross member 50 to which is fixed a top guide plate 52. Extending downwardly through the top guide plate is an actuator arm 54 having a rack of gear teeth 56 along one side. The lower end of the member 54 is fixed to an extraction plate 58 which has a pair of rotatable locking members 60 that are movable to secure the plate to a receptacle base unit 32. A drive gear 62 (FIG. 7) journaled on the cross member 50 and connected to a lever arm 64 is meshed with the gear rack 56 so that it will move the actuator arm upwardly by action of the ratcheted lever arm. Fixed to the top plate 52 is a anti slip-back means 66 which prevents any downward movement of the actuator arm between strokes of the lever arm. Extending through the top guide plate and the extraction plate are a plurality of plungers 68 each vertically aligned with the upper end of a probe element on the receptacle base unit. Near the upper end of each plunger is a retaining ring 69 which limits its downward movement. Spaced below the top guide plate is another retaining ring or washer 70 on each plunger and between this washer and the underside of the top guide plate around each plunger is a coil spring 72. Thus it is seen that each plunger is yieldable upwardly against the force of its coil spring. These plungers, assisted by their respective springs, function to dispense a viscous sealant from the probe elements as the extraction process takes place.

Turning to FIGS. 5 and 6 it is seen that the receptacle base unit 32 is comprised of a substantially rectangular sheet metal body 74 with channel-like members 76 at each end that each support a pair of spaced apart probe elements 34. Each probe element has an enlarged upper portion forming a cavity and surrounded by an non-conductive protective bushing 78 having an opening 80 to the cavity of the probe element. The elongated lower ends of the probe elements extend below the body of the base unit through its ground contacts 40 attached to the body. Thus, as shown in FIG. 6, the probe elements are relatively long and when installed they extend well into the laminated structure to make electrical contact with its internal conductive layers when the base unit is flush with the floor covering. As indicated in FIG. 5, the lower ends 82 of the plungers 68 are somewhat smaller in diameter than the openings 80 so as to extend through them and into contact with a piston-like plug 84 within the upper cavity of each probe element.

In each of the channel-like members 76 fixed to the body of the receptacle unit is a central elongated opening 86. At the lower end of each locking member 60 is an elongated lug 88 that is substantially the same shape but slightly smaller than the openings 86 in the channel-like members. Thus, when the locking members are positioned with their lugs 88 aligned with the base unit openings 86 they may extend downwardly through these openings. When the lugs are turned 90.degree. they bear against the channel-like members of the base unit thereby securing it to the extraction plate. The upper end of each locking member extends through the extraction plate and is pin connected to an annular member 90 supported on the upper side of the extraction plate. A transverse pin 92 extends from each locking member above its annular member, and the ends of these two pins are connected by a link 94 having a handle 96 that extends outwardly from the side of the tool. By moving the handle laterally both of the locking members and hence their locking lugs 88 can be rotated simultaneously relative to the receptacle base unit, thereby securing it to the extraction plate.

In FIG. 7, the locking members are shown with their lugs in the 90.degree. locking position relative to the base unit openings 86. The handle 96 is shown moved to its extreme right hand position against a pin stop 98 extending upwardly from the extraction plate. In one of the annular members 90 attached near an upper end of a locking member 60 is a radially extending stud 100 which is oriented to be parallel with the longitudinal centerline of the lug at the lower end of the attached locking member. When the lugs 88 are in their locking position, as shown in FIG. 7, the stud 100 is positioned in vertical alignment with a slot 102 formed in a safety bracket 104 fixed to the frame 48. As the tool is operated to extract a base unit and its probe elements, the extraction plate 58 is raised and the plunger springs 72 are compressed. As this occurs the stud 100 travels upwardly into the slot 102. This provides an important safety feature because at this point it prevents any rotation of the locking members and their lugs. This eliminates the possibility of any accidental release of the base unit from the extraction plate when the springs are compressed or loaded during an extraction cycle. Thus, the locking lugs can only be rotated to release a base unit when the springs are not compressed.

Now, describing the structural elements of tool 44 in somewhat greater detail with reference to FIGS. 12A and 12B, it is seen that the frame 48 is comprised of a pair of inverted V-shaped end members 106 extending upwardly from opposite ends of an opening 108 in the base plate 46. The upper cross member 50 is secured to the upper ends of these upright frame members by suitable fasteners such as machine screws 110 and the top guide plate 52 is secured to the cross member by similar screws.

As shown in FIG. 9, the actuator arm 54 extends through an opening 112 in the cross member 50 and is engaged by the drive gear 62 which is mounted on a shaft 114 journaled in a bearing 116 supported by the cross member. One end of the shaft extends outwardly from the bearing and has a connector fitting 118 adapted for attachment to a mating connector 120 on the operating lever arm 64. In the embodiment shown in FIG. 9 the shaft has a female connector adapted to receive the male connector of a standard ratchet-type wrench having the lever arm 64 extending from its connector end.

The upper end of the actuator arm 54 above the top guide plate extends through the anti-slip back device 66. As shown in FIG. 12B, this anti-slip back device is comprised of a friction bearing bar 122 having an opening 124 through which the actuator arm 54 extends. Opposite surfaces of the bar opening 124 engage adjacent opposite surfaces 126 of the actuator arm. The bar is pivotally mounted near its center on a bracket 128 that forms a fulcrum for the bar and is fixed to the top plate. Outwardly from the fulcrum point on the bracket is a spring member 130 connected to the bracket and the bar which urges its outer end upwardly away from the bracket and thereby urges its opposite surfaces into frictional contact with the sides of the actuator arm. Thus, as the actuator arm is moved upwardly by each driving stroke of the lever it readily slides relative to the inner surfaces of the bar opening. However, since the bar is held at a locking angle by the spring and bracket any tendency for the actuator arm to move downwardly between drive strokes of the operating lever arm is prevented by the friction or clamping action of the opposite contacting surfaces of the bar and the actuator arm.

In operation, when a receptacle base unit 32 and its probe elements 34 are to be removed from a laminated structure as shown in FIG. 2, the tool 44 is placed on the surface so that the receptacle base unit is positioned within the central opening 108 of the tool base plate. The handle 64 is now manipulated, as shown in FIG. 7, to lower the extraction plate 58 so that the lugs 88 extends through the openings 86 in the channel members 76 of the receptacle base unit, and the lugs are then turned 90.degree. by moving the locking handle 96 laterally. At this point the plunger springs 72 are compressed somewhat as the lower ends of the plungers 82 engage the piston-like plug 84 in each of the various probe elements (See FIG. 13). This initial or preloading force exerted on the probe element pistons is sufficient to start the immediate dispensing of a viscous sealant 132 within each probe element as the extraction process commences. Now, the operator may commence to move the lever arm 64 clockwise as shown in FIG. 7, causing the actuator arm 54 to move upwardly and thereby pulling the extraction plate 58 and hence the receptacle base unit 32 upwardly at the same time. As this upward movement of the extraction plate and the base unit continue, the plungers 82 move relatively further into the cavities at the upper ends of the probe elements. Actually, as the extraction plate moves upwardly, the plungers also move upwardly against their springs 72, but at a slower rate, and the springs provide a force on the plungers 82 which is sufficient to maintain a flow of sealant from the lower end of each probe element 34 that is adequate to fill the void created as it is withdrawn from the laminated structure. As illustrated in FIG. 14, each plunger 82 exerts an axial force on the piston plug 84 within the cavity of the probe element, thereby pushing the viscous sealant 132 downwardly from its storage cavity and through an elongated orifice 136 and out its lower end. As the probe members are withdrawn, each is disengaged from a tip member 138 at its lower end. These tip members may be made of a hard material such as metal or a ceramic and they are adhesively bonded to the probe members. During the installation of the receptacle base unit using a suitable impact tool, the adhesive bond between each tip 138 and its probe pin is wholly or partially destroyed, and the tip is gripped, after fully driven, by forces due to the enveloping (mostly radial) pressure of the deformed and compressed dielectric material of the laminated structure. An interlocking effect, which opposes probe pin withdrawal, is created by the pressure of the displaced dielectric material against part of the upper conical portion of the tip. However, since the gripping forces of the dielectric material are greatest on the tip member itself, the tip remains in its driven position when the probe pin is withdrawn and as soon as separation of each tip and pin occurs, sealant is dispensed.

To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.

Claims

We claim:

1. A tool for simultaneously withdrawing a plurality of probe elements from a planar structure into which they were previously driven, said tool comprising:

a fixed base adapted to lie flush against the surface surrounding a receptacle base unit supporting the probe elements to be withdrawn;

a frame attached to and extending upwardly from said base;

an extraction plate movable relative to said frame;

means on said extraction plate for locking it to said receptacle base unit;

an actuator arm fixed to said extraction plate and extending upwardly;

and drive means connected to said actuator arm for moving it upwardly, thereby applying a lifting force to said extraction plate and to the attached receptacle base unit.

2. The tool as described in claim 1 including elongated plunger means extending through said extraction plate and retained by said frame, said plunger means having lower end portions adapted to align with and engage movable members in said probe elements which operate to expel a viscous material from their lower ends as they are withdrawn.

3. The tool as described in claim 2 including a spring means engaging each said plunger means for allowing it to be yieldable axially to some degree while still exerting a force on the movable member of the engaged probe element.

4. The tool as described in claim 3 including a top guide plate supported on said frame, said guide being parallel to and spaced above said extraction plate, said plunger means extending through said guide plate while the upper ends of said spring means bear against it.

5. The tool as described in claim 1 wherein said actuator arm comprises a gear rack and drive means comprises a lever means, a circular drive gear sector meshed with said gear rack and mounted on a shaft journaled in said frame, and means for connecting said lever means to said shaft for turning said gear sector to move said actuator arm upwardly.

6. The tool as described in claim 5 including an anti slip-back means mounted on said guide plate for preventing backward movement of said actuator arm between strokes of said lever means.

7. The tool as described in claim 6 wherein said anti-slip back means comprises a pawl-like member having an opening through which the upper end of said actuator arm extends and edge surfaces of said opening for engaging opposite sides of said actuator arm, said pawl-like member being held at an angle to said actuator arm so that said edge surfaces provide a minimal friction as said actuator arm moves upwardly but provide friction sufficient to prevent movement of said arm in the opposite, downward direction between strokes of said lever means.

8. The tool as described in claim 7 wherein said pawl-like member is mounted on a fulcrum point between said opening at its inner end and its outer end, and spring means attached to said outer end for urging said edge surfaces of said pawl-like member against the sides of said arm.

9. The tool as described in claim 1 wherein said means for locking said extraction plate to a receptacle base unit comprises a pair of rod members extending downwardly through said plate and having lug members at their lower ends adapted to fit through similar shaped openings in the receptacle base unit, and means above said extraction plate connected to both said rod members for rotating them and their lug members simultaneously into a locking position with respect to the attached receptacle base unit.

10. The tool as described in claim 9 wherein said means for rotating said rod members simultaneously comprises a link member extending between and connected to radially extending means on each rod member, and a handle means fixed to said link member.

11. The tool as described in claim 9 including means for preventing said locking means from being unlocked once said tool has been operated to commence the extraction of a base unit with probe elements.

12. The tool as described in claim 11 wherein said means for preventing unlocking comprises means fixed to said frame having a slot, a projecting stud means on said locking means which becomes aligned with said slot when a receptacle base unit is locked to said extraction plate and consequently moves upwardly into said slot when the extraction process commences.

13. The tool as described in claim 12 wherein said means having a slot comprises a bracket fixed to one end of said frame and said stud means extends from sleeve member fixed to the upper end of one said rod member.