US008406112B2 (12) United States Patent (16) Patent N6; Merrill et al. (45) Date of Patent: (54) TURNTABLE (76) Inventors: George Earnest Merrill, Bartlett, TN (56) ( * ) Notice: . . . References Cited 3,218,081 A * 3,309,094 A * . 11/1965 Gentilini ..................... .. 369/267 3/1967 Stanton ....................... .. 369/269 3,786,288 A l/l974 Joannou 4,106,776 8/1978 A Subject‘ to any disclaimer, the term of this 4,202,551 A Patent 15 extended Or adJuSIed under 35 4,365,326 A * U.S.C. 154(b) by 0 days. 4,368,530 A (21) (22) Filed: (65) 12/1982 Ohsawa et a1. ............. .. 369/268 l/l983 Zopf 10/1984 Cooper et a1. 7/1985 Asano ...................... .. 369/4101 FOREIGN PATENT DOCUMENTS Prior Publication Data US 2012/0008488 A1 ' 1/1983 Darnall, Jr. 4,475,184 A 4,528,653 A * Jan. 4, 2011 G'll 5/l980 Diu?zl?lae‘lr‘ 4,369,950 A . Appl' NO" 12/984506 Mar. 26, 2013 US PATENT DOCUMENTS (US); Robert Edwin Williams, Memphis, TN (Us) . US 8,406,112 B2 Jan. 12, 2012 EP 0017004 Bl 7/1983 JP 55038666 A * 3/1980 * cited by examiner Primary Examiner * Thang Tran (51) Related US. Application Data Provisional application NO 61/292,029’ ?led on Jan 4 2010' ’ Int CL (52) us. Cl. ..................................................... .. 369/264 and armboard only Come into Contact With the elastomeric (58) Field of Classi?cation Search ..... .. 369/2644271 .1, layer’ which dampens energy’ allowing the turntable Produce the audio on the record Without excessive noise. (60) G11B 3/64 (200601) (57) ABSTRACT An improved turntable is described With inherent properties for reducing noise generated by external sources or by the parts of the turntable. The plinth of the turntable is comprised of an elastomeric layer and at least one stiffening layer that adds rigidity to the plinth. The support feet, spindle bearing, 369/2741, 248 See application ?le for complete search history. '5 O) O) // .~ ‘f,- 18 Claims, 5 Drawing Sheets ._,- f,» f f ///// 0 i.’ n‘ a US. Patent Mar. 26, 2013 Sheet 1 0f 5 US 8,406,112 B2 US. Patent Mar. 26,2013 Sheet 2 of5 US 8,406,112 B2 US. Patent R4ar.26,2013 Sheet30f5 US 8,406,112 B2 w@i US. Patent Mar. 26,2013 Sheet 4 of5 6"» Fig US 8,406,112 B2 US. Patent Mar. 26,2013 Sheet 5 of5 US 8,406,112 B2 FIG. 7 US 8,406,112 B2 1 2 TURNTABLE FIG. 5 is a cross sectional vieW of the tonearm mount as vieWed along line 5-5 of FIG. 2. FIG. 6 is an exploded vieW of the turntable plinth. CROSS-REFERENCES TO RELATED APPLICATIONS FIG. 7 is an exploded vieW of the turntable as a Whole. DETAILED DESCRIPTION This application claims the bene?t of US. Provisional Application No. 61/292,029 ?led Jan. 4, 2010 and incorpo rated herein by reference in entirety. The folloWing detailed description is presented to enable any person skilled in the art to make and use the invention. For purposes of explanation, speci?c details are set forth to pro FIELD OF THE INVENTION vide a thorough understanding of the present invention. HoW ever, it Will be apparent to one skilled in the art that these The present invention is generally directed toWard a neW speci?c details are not required to practice the invention. turntable With improved noise reduction properties. Descriptions of speci?c applications are provided only as representative examples. Various modi?cations to the pre BACKGROUND OF THE INVENTION ferred embodiments Will be readily apparent to one skilled in the art, and the general principles de?ned herein may be applied to other embodiments and applications Without departing from the scope of the invention. The present inven Turntables, also knoWn as record players, Work through the transduction of mechanical vibrations of the needle into an electrical signal Which can then be ampli?ed. Turntables are susceptible to various sources of noise and vibration Which 20 are ampli?ed along With the recorded sound, and Which can interfere With the enjoyment of the recording. The noise and vibration are “energy intrusions” that degrade the quality of signal produced by the turntable. tion is not intended to be limited to the embodiments shoWn, but is to be accorded the Widest possible scope consistent With the principles and features disclosed herein. Referring to the draWings, FIG. 1 illustrates an exemplary embodiment of the improved turntable. The turntable 1 con 25 sists of a rotating platter 2 that supports a phonograph record, There are three general sources of energy intrusion that a drive source 3 for this platter (such as a motor, pulley, and affect a turntable: airborne, mechanical, and internal noise belt), a plate (also knoWn as the plinth 7, base, or chassis) to mount the bearing 4 for the rotating platter 2, motor mount ing, andpickup arm mounting. Support feet 8 are used to raise generated by the turntable itself. Airborne energy contained Within the environment includes sounds that cause the tum table to vibrate. These vibrations are picked up by the tum 30 and support the plinth 7 While further reducing intruding table and ampli?ed. Mechanical noise includes vibrations from the environment that travel through the support feet of energy. the record player. For example, nearby tra?ic, subWays, con material. In a preferred embodiment it is made of a compound struction, or even footsteps Will cause the turntable to vibrate. Finally, a turntable has its oWn internal sources of energy The rotating platter 2 can be manufactured from any solid containing Bakelite, cellulose and resin. This compound has 35 Which Will be ampli?ed and negatively affect the sound. These include energy generated from the motor, drive system, s1on. Preferably a rubber cork compound mat is used to place the platter support bearings, and tone arm release energy as Well as energy generated by stylus to groove contact during track ing of the record. The presently disclosed turntable solves the problem of unWanted noise by isolating the intruding energy. The reduc a high density, a loW resonance top, and dimension stability. These characteristics make it ideal for reducing energy intru record upon the rotating platter 2, thus aiding to quell vibra 40 tions Within the vinyl as the stylus 26 is tracking the grooves of the record. HoWever, a felt mat or rubber mat may also be employed. The rotating platter 2 design and material consideration tion in energy intrusions results in a cleaner signal. along With the mat control the internal energy that is gener SUMMARY OF THE INVENTION 45 ated by the stylus 26 making contact With the grooves of the record during tracking. In one embodiment, the platter shaft 9 is manufactured from precision ground stainless steel With a hardened thrust ball placed at the end. The platter is supported by a bearing 4 An improved turntable With vibration isolating properties is disclosed. This improved turntable reduces vibration through a unique plinth material, internal bracing, and vibra tion absorbing feet. As a result, the turntable reproduces the recorded audio more faithfully and Without unWanted noise. 50 face is provided at the bottom of this bearing 4 to alloW the shaft thrust ball to ride With virtually no friction, thus pre The claimed device comprises a turntable With a plinth made of composite material With both ?rm and elastomeric layers, a noise reducing platter, internal bracing, and noise reducing feet. manufactured from graphite impregnated nylon or preferably molybdenum disul?de impregnated nylon. A hardened sur 55 venting additional noise. The plinth 7 also greatly reduces energy intrusion. The plinth 7 is the heart of the turntable that supports all three energy generating parts: the motor, bearing/ spindle, and tone BRIEF DESCRIPTION OF THE DRAWINGS arm. Further advantages of the invention Will become apparent by reference to the detailed description of preferred embodi ments When considered in conjunction With the draWings: FIG. 1 depicts a perspective vieW of the turntable. The plinth 7 has a novel construction that signi?cantly 60 other elastomer sandWiched betWeen stiffening layers 10. FIG. 2 is a top plan vieW of the turntable. FIG. 3 is a cross sectional vieW of the feet as vieWed along line 3-3 of FIG. 2. FIG. 4 is a cross sectional vieW of the turntable as vieWed along line 4-4 of FIG. 2. reduces energy intrusion. As can be seen in FIG. 6, the plinth 7 is constructed from a laminate of an elastomeric layer 11 or 65 The elastomeric layer is preferably a dense rubber With a durometer of 80, but any elastomeric material may be used. This stiffening layers 10 are preferably made of a hard mate rial. such as carbon ?ber, aluminum, or plyWood. The elasto meric layer 11 absorbs vibration and energy, While the stiff US 8,406,112 B2 3 4 ening layer 10 provides structure and support. The operating The ?at of the hemisphere is placed in a support base 17 to alloW retention of its shape and for uniform input of energy into the foot. The feet are designed such that only elastomeric portions of the feet come into contact With the elastomeric parts of the turntable that produce energy, such as the motor, spindle, and tonearm do not come into contact With the stiff ening layer 10. Instead, the stiffening material is cut aWay from the laminate, and these operating parts are attached directly to the elastomeric layer 11. The space betWeen the operating parts and the sideWalls of the stiffening material is 5 cantly dampened. Airborne energy is dampened by the overall energy absorb ing capability of the laminate 7, feet 8, and rotating platter 2. knoWn as energy isolation valleys 12. These gaps in the stiff As a result, the Whole turntable is virtually impervious to airborne energy encountered in a normal listening environ ening layer 10 of the laminate material prevent the operating parts from transmitting energy directly to the stiffening layers 10. Vibrational energy travels easily through hard material Without signi?cant dampening. HoWever, vibrational energy ment It should be understood that features of any of these embodiments may be used With another in a Way that Will noW does not travel Well through elastomeric materials because the elastomeric materials absorb much of the energy. The unique composite laminate material of the plinth 7 absorbs vibrational energy While providing rigidity to support the platter. The advantage of this system is that energy developed by each of these operating parts is only transmitted through the elastomeric layer 1 1, and is absorbed and dissipated by the elastomeric layer 11 before it can intrude and affect the other parts. For example the motor energy is dissipated before it can affect the energy release from the pickup arm. To reduce the possibility of sagging, spar bracing 18 may also be introduced into the elastomeric layer 11 of the lami nate to further support the Weight of a heavy platter. In an be understood in vieW of the foregoing disclosure. Although the present invention has been described and illustrated With respect to at least one preferred embodiment and use therefor, 20 25 2. The turntable of claim 1 further comprising an armboard mounted Within said energy isolation valley. 30 and bottom aluminum stiffening layers respectively, thus increasing the rigidity of the plinth. 5. The turntable of claim 1 further comprising a spindle bearing mounted Within said energy isolation valley. 35 meric layer 11. As can be appreciated by FIG. 4 and FIG. 5, 7. The turntable of claim 1 further comprising stiffening material connected to said stiffening layer. 8. The turntable of claim 1 further comprising a rotating 40 9. The turntable of claim 1 further comprising a mat com posed of a material selected from the group consisting of rubber cork compound, felt, and rubber. 45 three directions so that the armboard 19 is parallel to the rotating platter 2. Mechanical energy intrusion from the surface that the tum table 1 rests upon is managed by a system called the isolation support foot 8 Which consists of an inverted hemisphere 14 consisting of an elastomeric material. An adjustable support column 13 is attached to the elastomeric layer 11 of the plinth 7 and is resting upon a inverted hemisphere 14, preferably made of highly absorbent rubber. This support column 13 utiliZes a positioning pin to hold the foot 8 in place. The support column 13 consists of tWo parts: the height adjust ment collar 15 and the hemisphere coupler With positioning pin 16. A bolt is inserted through a compressing Washer and the plinth elastomeric layer 11 into the hemispherical coupler, draWing the adjustment collar 15 and hemispherical coupler 16 tightly together. This creates a support column 13 that is extremely solid While still having height adjustment capabili ties. The curved face on the hemispherical coupler 16 varies contact With the inverted hemisphere 14 Which changes the spring rate, further helping to subdue energy transmission. platter composed of a compound containing Bakelite, cellu lose, and resin. stiffening layer 10 around it. This isolation valley 12 prevents the armboard from coming in contact With the stiffening layer 10. Upper armboard 19 is secured to loWer armboard 24 by fasteners that pass through elastomeric layer 11. These fas teners alloWs for easy adjustment of the arm mounting in all 6. The turntable of claim 1 further comprising internal bracing in said plinth. the tone arm 28 is mounted to an upper armboard 19. The upper armboard 19 rests directly on the elastomeric layer 11 in an area that is absent of stiffening layers 10. An isolation valley 12 exists betWeen the upper armboard 19 and the 3. The turntable of claim 1 further comprising a drive source mounted Within said energy isolation valley. 4. The turntable of claim 1 further comprising a support foot mounted Within said energy isolation valley. The tone arm mounting system accomplishes the dissipa tion of tonearm release energy by using an energy transfer isolation valley is an area of said plinth that is not in contact With said stiffening layer. truss. For example, in one embodiment a 1.25 inch aluminum tonearm mounting platform coupled to the damping elasto it is not to be so limited, since modi?cations and changes can be made therein Which are Within the fully-intended scope of the invention. We claim: 1. A turntable comprising a plinth Which is further com prised of an elastomeric layer and a stiffening layer, Wherein said stiffening layer is in contact With said elastomeric layer except in an energy isolation valley, Wherein said energy alternative embodiment, added stiffening material may be used to directly connect the stiffening layers 10 to form a rigid cylinder strut is placed through a hole in the elastomeric layer 11 and the top and bottom of the cylinder are glued to the top portion of the turntable, thus ensuring that energy is signi? 10. The turntable of claim 1 further comprising a platter shaft composed of stainless steel. 11. The turntable of claim 2 Wherein adjustable fasteners are used to mount said armboard Within said energy isolation valley. 50 12. The turntable of claim 4 Wherein said support foot is composed of an elastomeric support material. 13. The turntable of claim 12 Wherein said elastomeric support material is in the shape of an inverted hemisphere. 14. The turntable of claim 4 Wherein said support foot 55 further comprises an adjustable height column. 15. The turntable of claim 5 Wherein said spindle bearing is composed of molybdenum disul?de impregnated nylon. 16. The turntable of claim 5 Wherein said spindle bearing is composed of graphite impregnated nylon. 60 17. The turntable of claim 15, Wherein the plinth further comprising internal bracing. 18. The turntable of claim 15, Wherein the plinth further comprising stiffening material connected to said stiffening layer.