US3433444A - Counterpoised supporting device - Google Patents

Description

March 18, 1969 T. F. sMn-H COUNTERPOISED SUPPORTING DEVICE Sheet l of 2 Filed Jan. 4, 1967 INVENTOR. THOMAS E. SMITH 6AM, KM ,/W 7")4f/'0rn (yf VIII/I March 18, 1969 T. F. SMITH COUNTERPOISED SUPPORTINGDEVICE Sheet 0f 2 Filed Jan. 4. 1967 INVENTOR. THOMAS F'.. SMITH United StatesPatent O 12 Claims ABSTRACT OF THE DISCLOSURE A `supporting device having a counterpoised, elongated arm assembly with an upper end mounted to a downward facing supporting surfa-ce and a lower suspended end adapted to hold a tool and movable between raised and lowered positions. A spring -member is arranged at the upper end of the arm assembly to provide a balancing force so that the tool holding end is normally in the raised position. The arm assembly is mounted for movement about an axis perpendicular to the supporting surface and has a clamping device to lock the arm in a selected position relative to the perpendicular axis. A second clamping device is operable to lock the tool in a selected orientation relative to the supporting surface.

Backgronnd of the invention This invention relates to supporting devices and more specifically to an elongated supporting arm assembly having an upper end mounted for pivotal and swiveling movement relative to a supporting surface. The opposite end of the supporting arm is adapted to carry a tool which may be locked or maintained in a predetermined orientation relative to the supporting surface. The arm assembly is counterbalanced so that the tool is suspended in a spaced position relative to a working surface.

Balanced supporting arm assemblies are useful for suspending tools such as X-ray units, dental tools, and the like and are normally arranged so that the user may swing the tool into a working position when in use and then swing the tool out of the way when its use is not required. Conventional balanced supporting assemblies employ a balancing arrangement wherein a spring-biased member is mounted to provide a force on the supporting arm assembly in opposition to the weight of the arm assembly and the tool which is attached thereto. Thus, the tool is suspended in the air and movable between positions toward and away from a working station. An example of a support of the prior art illustrating the above features is disclosed in Patent No. 2,837,307 issued June 3, 1958 to G. W. Schwager et al.

One feature necessary in balanced supporting arms is the ability to lock the tool in a predetermined orientation relative to the supporting surface and to maintain this orientation as the tool is swung into and out of a working position. In addition the tool supporting means must permit the orientation of the tool to be readily changed. These features have been partially achieved in the prior art by utilizing a parallelogram form of linkage having a suspended tool holder arranged to remain at a constant orientation relative to the supporting surface throughout the full arc of the arm assembly. However, such prior art devices normally require an elaborate, cumbersome, mechanical means for establishing the supporting arm in all of its various positions.

Summary The preferred embodiment of the present invention, which will be subsequently described in detail, solves the aforementioned problem and in addition provides `some special advantages for suspending a tool at a work station. The preferred embodiment is described with referice ence to a food mixing appliance and is useful in suspending such an appliance in the kitchen preferably to the under side of a cabinet or the like.

The utility of the present invention manifests itself Iby suspending the mixing appliance in a raised position so that the user does not have to bear the weight of the appliance. In addition, the appliance is suspended by the supporting arm such that it is movable toward and away from the other side of the supporting surface. Normally the appliance is suspended in a raised position adjacent the supporting surface so that it is out of the Way of the user. It can be lowered by a slight downward force so that the working elements of the appliance come into engagement with the contents -of the mixing bowl.

The preferred embodiment includes an elongated arm assembly, means for anchoring one end of the arm assembly to the supporting ysurface and means for attaching the appliance to the opposite end of the arm assembly. The anchor means includes a pivot supporting the arm assembly for movement about a horizontal axis. The pivot is mounted in a novel spring loaded clamping arrangement that permits rotation of the arm assembly in its raised position, but prevents rotation in the lowered working position of the tool.

One preferred form 'of the supporting arm assembly comprises a parallelogram type of linkage including a pair of spaced apart parallel `supporting arm members and an elongated stabilizing arm member. The free end of the stabilizing arm is pivotally attached to the tool supporting member. The supporting arms are also pivotally connected to the tool supporting member by a pin arranged to clamp the tool ysupporting member rigidly between the supporting arms so that the arm assembly forms a rigid unit.

Another preferred form of the present invention contemplates a telescopic arm assembly which may be locked at a selected extended position. The tool holder is pivotally attached to the unsupported end of the arm assembly for movement about a horizontal axis. A rod, supported for rotation about an axis parallel to the longitudinal axis of the arm assembly, has a pair of gears, one at each end. One gear meshes with a toothed section of the tool holder and the opposite gear meshes with a toothed sector of the supporting lug. Raising and lowering of the arm assembly causes the rod to rota-te and pivot the tool holder throigh an angular displacement compensating for the swing of the arm so that the tool remains constantly oriented relative to a fixed working surface.

Preferably, the tool holder has an electrical jack coupled with the tool which permits rotation of the tool holder relative to the supporting arm without the problem of entangling electrical lines.

It is, therefore, an object of the present invention to provide an improved counterbalanced, supporting arm assembly having an elongated arm unit with one end pivotally mounted to a supporting surface by a releasable clamping connection and the other end adapted to carry an appliance for movement between spaced positions toward and away from the supporting surface.

It is another object of the present invention to improve balanced arm assemblies by providing means for clamping a tool supporting member in a selected orientation relative to the supporting surface.

It is a still further object of the present invention to improve balanced arm supporting devices by providing such a device having an arm unit which carries -a tool supporting member having a coupling for supportably engaging the tool and which furnishes a connection from a source of electrical energy to the tool.

Still another object of the present invention is to increase the utility of suspended arm assemblies wherein the tool may be moved through arcs of varying radii relative to the mounting connection by providing an extensible arm assembly comprising a pair of telescopically associated arm sections.

It is -a still further object of the present invention to :provide a ba'lanced supporting arm assembly which. carries a selforienting appliance holder.

Still another object of the present invention is to provide an arm rassembly having a rst end pivotally attached to a supporting surface, an opposite tool-supporting end, and means for self-orienting a tool relative to the supporting surface as the arm pivots toward and away from the supporting surface by providing a shaft member supported for rotation by the arm unit and having an upper end engaged with the supporting bracket to produce rotation responsive to relative movement between the arm and supporting surface, and the lower opposite end engaged with the tool holder and operative to produce a complementary movement between the tool holder and the supporting surface.

Still further objects and advantages of the present invention will readily occur to one skilled in the art to which the invention pertains upon reference to the following detailed description.

Brief description ofthe draifvngs The description makes reference to the following drawings in which like reference characters refer to like parts throughout the several views and in which:

FIGURE 1 is a perspective view illustrating a preferred arm assembly mounted to the underside of a supporting surface and movable toward and away from a raised position illustrated in phantom;

FIGURE 2 is an elevational view of the supporting arm assembly illustrated in FIGURE 1 as seen substantially from the tool holder looking toward the arm as sembly with parts in section for purposes of clarity;

FIGURE 3 is a view of the Vpreferred arm assembly illustrated in FIGURE 1 in its extreme lowered position,

FIGURE 4 is a modified form of the arm assembly illustrated in FIGURE 1 with the appliance holder adapted for transmitting electrical energy to the appliance;

FIGURE 5 is a modified embodiment of an arm as sembly illustrating the present invention;

FIGURE 6 is an enlarged, fragmentary, transversw sectional view taken along lines 6-6 of FIGURES 5; and

FIGURE 7 is a sectional view taken along line 7-7 of FIGURE 5.

Description of the preferred embodiments Now referring to FIGURES 1-3, the improved supporting device comprises a pair ofannular plates 10 and 12 mounted by threadedfasteners 14 to the underside of acabinet 16. A circular supportingplate 18 is disposed in the opening defined by theannular plates 10 and 12 and carries a plurality oflips 20. Thelips 20 are slidably disposed in an annular slot dened byplates 10 and 12. Alug member 21 depends downwardly from theplate 18 and is provided with anaperture 22 adjacent theplate 10.

Anannular locking ring 23 is xed to theplate 12 and has downwardly directed teeth which are adapted to mesh with the teeth of acompanion locking ring 24. Thelocking ring 24 is adapted to be engaged with or released from thelocking ring 23 and has an elongated flat spring member supported thereto at diametrically opposite lower portions. The midportion 28 of aspring 26 extends through theaperture 22 in thelug 21 and has a width slightly less than the width of theaperture 22. Theaperture 22 is dimensioned to permit the midportion 28 of thespring 26 to freely flex therein. Thelug 21 can be rotated relative to themounting plate 12 by lifting thelocking ring 24 away from thelocking ring 23 rotating thelug 21 to any desired orientation and then permitting thelocking ring 24 to snap into engagement wtih the fixedlocking ring 23 to prevent the lug from rotating.

A pair ofarm sections 30 are pivotally attached to thelug 21 by apin 32. Thearm sections 30 each have anupper end portion 34 which are slightly bent towand one another and contoured to engage thespring member 26 adjacent its midportion 28 when thearm sections 30 are in a lowered position.

Anappliance holder 36 is sandwiched between the free ends of thesections 30 and has a thickness slightly less than the normal spacing therebetween.

A pivot means 37 connectsarms 30 to theappliance holder 36.

An elongated stabilizingarm member 38 is also disposed between thearm sections 30 with an upper end pivotally attached by apin 40 to thelug 21 and its lower opposite en'd attached for pivotal movement to theappliance holder 36 by apin 42. Thearm sections 30 and the stabilizingarm 38 have a length chosen so that withlthe lug 21 and theappliance holder 36 they constitute a parallelogram type of linkage. Thearms 38yand 30 can be pivoted between raised and lowered positions relative to thecabinet 16 so thatappliance holder 36 maintains a constant orientation relative tocabinet 16 in all positions ofarms 30 and 38.

The pivot means 37 comprises a cooperatingfemale pin element 44 and amale pin element 46. Thefemale pin elment 44 has an enlarged head and is fixed to one of thearm sections 30 so that an internally threaded section extends between thearm sections 30. Thelmale pin element 46 is threadably engaged with the female 'section 44 and has an outerenlarged end 48 in abutment with thecompanion arm section 30. Theenlarged end 48 terminates in ahandle section 50.

By rotating thehandle section 50 in a counterclockwise direction as viewed in FIG. 3, the male andfemale pin elements 44 draw thearm sections 30 toward one another so that they clamp theappliance holder 36 between them to form a rigid arm unit at any selected inclination relative to thecabinet 16. By rotating thehandle 50 in the opposite direction, the arm direction, thearm isections 30 are separated from theapplicance holder 36 so that it may be pivoted about itsclamping pin elements 44 and 46.

As thus far described, it is obvious that the improved supporting device may be swiveled in an arc of 360 about an axis generally normal to the supporting surface provided by thecabinet 16 by raising thearms 30 so that upper ends 34disengage spring 26 thereby permitting the separation of locking rings 23 and' 24. Lowering of thearms 30 engagesrings 23 and 24 so that the arm assembly is locked in place. Theappliance holder 36 may be swung toward or away from thecabinet 16 and locked at yany selected lowered position by the cooperating lockingpin elements 44 and 46.

Theappliance holder 36 is preferably provided with abent end section 52 carrying a plurality of stepped sections arranged in an annularly spaced arrangement and intended to engage a complementarily formed stepped arrangement carried thy theappliance 50. Thus theappliance 50, when mounted on thebent end portion 52, is locked in place against rotation relative to the supportingmember 36.

FIG. 4 illustrates a modification of the preferred embodiment wherein thearms 30 and 38 carry anappliance holder 56 having a pinelectrical plug 58 engagable with asocket 60 carried by theappliance 62. Theplug 58 haselectrical leads 64 connected to anelectrical conduit 66 embedded in the supportingmember 56 with a midportion supported in a `grommet 68 carried by one of the supportingarms 30. Theconduit 66 terminates at an electrical coupling '70. In this form of the invention, theappliance 62 is mounted on the sup-portingmember 56 to complete an energizing electrical circuit so that theappliance 62 can be rotated in a. variety of working positions without becoming entangled with the electrical cords which supply the electrical cords which supply the electrical energy.

FIGS. 5, 6 and 7 illustrate lstill another embodiment of the invention comprising an extensible supporting arm assembly generally indicated at 72 and mounted on the underside of the supportingstructure 16 by mountingmeans 74. The mounting means 74 is the same as the mounting means illustrated in the embodiment of the invention as shown in FIG. 1 and includes theannular mounting plates 10 and 12 attached by threadedfasteners 14 to thestructure 16. Theadjustable locking ring 24 carries a flat,resilient spring 26 and is engagalble with thefixer locking ring 23.

A circular mounting plate 76 is disposed within the aperture defined by theplates 10 and 12 and has a plurality offingers 78 slidably seated in the annular slot defined by theplates 10 and 12 to permit the plate 76 to rotate in an arc of 360. A downwardly depending lug 82 is carried by the plate 76 and carries a pair of olppositely directedjournals 84.

Theextensible arm assembly 72 comprises a tubularinner arm section 86 which is telescopically associated with a. tubularouter arm assembly 88. The opposite side walls of theinner arm assembly 86 are engaged for pivotal movement to thejournals 84 so that thearm section 86 may pivot between an upper substantially horizontal position to a downwardly generally vertical position. Theinner arm section 86 has a length extending upwardly to provide an abutment surface 90. The abutment 90 engages thespring 26 in the same manner as thearm sections 30 engage thespring 26 to releasably lock rings 23 and 24 as illustrated in FIGS. 1 and 2.

Theouter arm assembly 88 is movable relative to theinner arm assembly 86 between extenlded and retracted positions. Apin 92 at the free end of the arm assembly support-s a tool holder y94. Thetool holder 94 is then supported for rotation relative to anarm assembly 88.

Acoil spring 95 is wrapped around one of thejournals 84 with oneend 95A engaging theupper arm assembly 86 and itsopposite end 95B reacting against a rpin 95C carried by the lug 82. This arrangement urges thearm assembly 72 to a normal raised position where theappliance holder 94 does -not interfere with the activities of the user. By applying a slight downward force on theappliance holder 94, it can be lowered to any selected working position.

It is frequently desirable that theappliance holder 94 maintain a constant orientation relative to a fixed working surface in all positions of the supportingarm assembly 72. For this reason a pair of cooperatingshaft sections 96 and 98 are provided.Shaft section 96 has a narrowed section supported for rotation by abearing 100 fixed to thearm section 88 and adjacent arounded section 102 of theappliance holder 94. Theshaft section 98 is journaled for rotation in abearing 104 fixed toarm section 86 adjacent the periphery of the lug 82. Theshaft sections 96 and 98 are locked inbearings 100 and 104 against longitudinal movement.

Theshaft section 96 has a longitudinal andoctagonal bore 106 running from its inner end.

Theshaft section 98 is milled with anoctagonal cross section 108 corresponding to thebore 106 of thecompanion shaft section 96.

The lengths of thebore 106 and the milledsection 108 are such that they provide engagement of theshaft sections 96 and 98 between the fully extended and retracted positions of thearm sections 86 and thearm section 88.

A lockingmember 112 is carried on the inner side of thearm section 88 and adjacent its inner end. Theblock 112 is provided with abore 114 which journals the end toshaft section 96. The lockingmember 112 has a lateral threaded bore 118 to receive a threaded lockingmember 120, lockingmember 120 between a locking position wherein its inner end abuts one of the at surfaces of theshaft 98 and an unlocked position wherein its inner end is slightly spaced from theshaft section 98 to permit relative longitudinal sliding movement between theshaft sections 98 and 96.

Theinner arm member 86 has alongitudinal slot 116 which as can best be seen in FIGURE 6 accommodates the lockingmember 112 when thearm sections 86 and 88 are moved between extended and retracted positions.

Ahandle member 122 is fixed t0 the outer end of the threaded lockingmember 120 and provides means for applying a force to the locking member 1'20 for rotation into or out of a locking position withshaft 98.

It can be seen that when the threadedmember 120 is in its locked position, it not only prevents relative rotation between theshaft sections 96 and 98, but also locks thearm sections 86 and 88 against longitudinal movement. Thus thearm assembly 72 can be extended or retracted to a selected length and rigidly locked at that length.

The upper end of theshaft 98 carries abevel gear 124 which meshes with a toothed section 126 formed adjacent the periphery of the lug 82.

When thearm sections 86 and 88 are pivoted between lowered and raised positions, thebevel gear 124 produces rotation of thecompanion shafts 96 and 98.

The outer end of theshaft section 96 carries asimilar bevel gear 128 in mesh with atoothed section 130 formed adjacent therounded section 102 of theappliance holder 94. Thetoothed section 130 is identical to the toothed section 126. Thus rotation of theshafts 96 and 98 produces a pivoting of the supportingmember 94 about thepin 92.

The angular movement of theappliance holder 94 relative to the supportingarm assembly 72 corresponds to the angular movement between the supportingarm assembly 72 and the fixed lug 82. Thus theappliance holder 94 is always at a constant orientation relative to a fixed surface as thearm assembly 72 moves between its raised and lowered positions.

Although I have described two preferred embodiments of the present invention it is to be understood that various modications and revisions can be made therein without departing from the spirit of the invention as described in the scope of the claims.

I claim:

1. A supporting device for mounting a tool to a supporting structure, comprising:

(a) an elongated arm assembly;

(b) means on a first end of the arm assembly for mounting a tool;

(c) means for mounting the other, second end of the arm assembly -to a supporting structure for a first motion in which the first end of the arm assembly is movable in a circular path about an axis normal to the supporting structure, and a second motion in which the first end of the arm assembly is movable toward and away from the supporting structure between a raised position and a lowered position;

(d) counterpoise means biasing the arm assembly so that its first end is urged toward its raised position, said counterpoise means being operative to suspend a tool mounted on a first end of the arm assembly when the first end is in its lowered position;

(e) means for restraining the motion of the arm assembly from a selected orientation with respect to said normal axis comprising:

(l) a first locking member having a series of teeth formed about a common center, and means for iixedly mounting said first locking member so that its teeth are supported concentrically with respect to the normal axis about which the arm assembly is movable in its first motion;

(2) a second locking member having a series of teeth engageable with the teeth of the first locking member;

(3) means for supporting the second locking member between the arm assembly and the supporting structure for motion with respect to the first locking member between a first position in which the teeth of the two locking members are engaged to prevent rotation of the second locking member with respect to the first locking member about said normal axis, and a second position in which the second locking member is rotatable with respect to the first locking member about said normal axis;

(4) means connecting the second locking member to the arm assembly so that the lsecond locking member is fixed against rotation about said normal axis with respect to the arm assembly; and

(5) means on said arm assembly engageable with the second locking member for moving the second locking member to its first position as the first end of the arm assembly is lowered from its raised position, and for allowing movement of the second locking member toward its second position when the first end of the arm assembly is in its raised position,

whereby the arm assembly can be swung with its first end in its raised position about said normal axis to a selected orientation with respect to said normal axis and then restrained in the selected orientation by moving the first end of the arm assembly to its lowered position.

2. A supporting device as defined in claim 1, wherein said arm assembly comprises a pair of telescopically associated arm sections including an innermost and an outermost arm section interengaged for relative movement between an extended length and a retracted length, and including mean for locking said arm sections one to the other with the first end of the arm assembly at a selected length from the mounting means for said arm assembly.

3. A supporting device as defined inclaim 2, in which the means for mounting a tool on the first end of the arm assembly include a supporting member carried at the free end of the outermost of said arm sections and supported for pivotal movement relative to said outermost arm section, means on said supporting member providing a series of teeth formed at a common radius about the axis of said pivotal movement, a lgear member meshed 'with said teeth, a shaft supporting said gear member for rotation as the supporting member moves with respect to said outermost arm section; means journaling said shaft to said outermost arm section; and means for releasably locking said shaft against rotation so that said supporting member may be locked in a selected relative position with respect to said voutermost arm section.

4. A supporting device as defined in claim 3, including a second supporting member having a series of teeth formed at a common radius about the axis of pivotal movement between the innermost arm section and said second .supporting member, a second gear member carried by said shaft meshed with the teeth of said second supporting member, and means for fixedly supporting the second supporting member with the support so that the first support member maintains a constant orientation with the second support member as the arm assembly is moved between its raised and lowered position.

5. A supporting device as defined in claim 4, wherein said releasable locking means compirses said shaft having a flat peripheral surface, a threaded member carried by one of said arm sections, said threaded member being operable to engage said fiat surface to prevent rotation of said shaft.

6. A supporting device as defined in claim 1, in which the mounting means for the arm assembly supports the first end of the arm assembly so that its second motion is toward and away from a lowered position that is below the second end of the arm assembly.

7. A supporting device as defined in claim 1, in which said arm assembly comprises:

(a) a first member connected to the mounting for said arm assembly and provided with a pair of spaced pivots;

(b) a pair of elongated arms each having upper and lower ends, the upper end of each of said pair of arms being connected to one of said pivots so that each arm is movable about its respective pivot;

(c) a tool-supporting member;

(d) means providing a pivotal connection between the lower end of each of said arms and said tool-supporting member so that said first member, said pair of elongated arms and said tool-supporting member form a parallelogram linkage; and

(e) means on one of the pivotal connections for locking one of the arms against motion with respect to the tool-supporting member so that the tool-supporting member can be locked in a selected position with respect to the first member.

8. A supporting device as defined in claim 7, wherein the last mentioned means comprises a pair of cooperating, interlocking elements forming one of the pivotal connections between the tool-supporting member and the lower end of one of said arms, said interlocking elements having portions for clamping the arm and the tool-supporting member together to lock them against relative movement.

9. A supporting device as defined in claim 8, wherein said tool-supporting member has a coupling section for mating with a complementarily formed coupling section carried by said tool for the transmission of electrical energy through said tool-supporting member and to said tool.

10. A supporting device as defined in claim 1, in which the first and second locking members comprise a pair of annular members each having a planar series of teeth formed in an annular array, one of said annular members being adapted for a fixed attachment to the support structure with its teeth facing away from the support structure, the second annular member being supported adjacent the first annular member with its teeth confronting the teeth of the first annular member, and an elongated spring member spanning the second annular member with its ends engaged with opposite sides of the second annular member, and means on the arm assembly engaged with the mid-section of the spring to bias the second annular member toward the first annular member.

11. A supporting device for mounting a tool to a supporting structure, comprising:

(a) a support adapted for attachment to a supporting structure;

(b) an elongated arm assembly formed of a pair of arm sections telescopically joined together for relative motion between extended and retracted positions;

(c) means for locking said arm sections together with one end of said arm assembly at a selected distance with respect to the opposite end of said arm assembly;

(d) means for pivotally connecting one end of said arm assembly to said support so that the opposite end of said arm assembly can be moved between a raised position and a lowered position;

(e) a tool supporting member pivotally carried on the opposite end of said arm assembly;

(f) means on said arm assembly connecting said toolsupporting member and said support so that said toolsupporting member maintains a predetermined orientation with respect to said support as the opposite end of the arm assembly is moved between its raised and its lowered positions; and

(g) counterpoise means for biasing the opposite end of the arm assembly toward its raised position, said counterpoise means being operative to suspend a tool carried on the tool-supporting member when the opposite end of the arm assembly is in its lowered position.

12. The combination as defined in claim 11, in which the means for connecting the tool-supporting member to the support comprises:

(a) an elongated shaft assembly including a pair of telescopically joined shaft members connected to one another for rotation;

(b) means journaling one of said shaft members to one of said arm sections and the other of said shaft members to the other of said arm sections;

(c) rst gear means connecting one end of said shaft assembly to the tool-supporting member so that the tool-supporting member moves between pivoted positions with respect to said arm assembly as said shaft assembly is rotated; and

ing member can be supported at a selected distance from the support and is pivoted with respect to the arm assembly as the arm assembly is pivoted with respect to said support.

References Cited UNITED STATES PATENTS 510,147 12/1893 TarbOX 248-281 1,685,718 9/1928 Murdoch 248-284 XR 2,648,146 8/1953 Foster.

ROY D. FRAZIER, Primary Examiner.

(d) second gear means connecting the opposite end of 15 I- FRANKLIN FOSS Assistant Examinersaid shaft assembly to said support so that the shaft assembly is rotated as the arm assembly is pivoted with respect to said support whereby the tool-support- U.S. Cl. X.R.

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