US3826559A - Adjustable tension control means for microscopes - Google Patents

Abstract

Coarse adjustment tension control means have been provided in a microscope in connection with the coarse adjustment control to permit the regulation of friction upon the coarse adjustment according to the users focusing preference and as well by the same control means permit frictional locking of the coarse control mechanism to the vertically-adjustable block on the vertically extending arm and the specimen platform so that it need not float or settle by gravity. This tension control adjusts for wear upon the coarse control and gears. A turn-knob is provided upon a gear housing extending through the main block that is actually adjustable upon a supporting bracket for the coarse adjusting pinion gear that meshes with a rack on the upstanding arm of the microscope and this knob engages with a plurality of short rods that slide through the bearing support plate by a turn knob and engage with a longitudinally shiftable ring having a plastic friction washer adapted more or less for engagement with a cooperating flange of the coarse adjustment gear case to thereby control the tension and permit the locking of the coarse adjustment control parts in their adjusted positions.

Description

United States Patent Berliner et al.

[11] 3,826,559 [451 July 30, 1974 ADJUSTABLE TENSION CONTROL MEANS FOR MICROSCOPES [75] Inventors: Emanuel R. Berliner, New York;

Harukichi Ishii, Tokyo, Japan [.73] Assignee: Bristoline Inc., Island Park, NY.

[22] Filed: Jan. 3, 1973 [21] Appl. N0.: 320,707

2,560,169 7/1951 Gradisar 350/84 X 2,820 396 l/l958 Prcssey 350/84 3,355.955 l2/l967 Aller 350/86 X 3,451,739 6/1969 Fitzglbbons 350/84 Primary Examiner-David H.'Rubin Attorney, Agent, or Firm-Laforest S. Saulsbury, Esq.

[5 7] ABSTRACT Coarse adjustment tension control means have been provided in a microscope in connection with the coarse adjustment control to permit the regulation of friction upon the coarse adjustment according to the users focusing preference and as well by the same control means permit frictional locking of the coarse control mechanism to the vertically-adjustable block on the vertically extending arm and the specimen platform so that it need not float or settle by gravity. This tension control adjusts for wear upon the coarse con trol and gears. A turn-knob is provided upon a gear housing extending through the main block that is actually adjustable upon a supporting bracket for the coarse adjusting pinion gear that meshes with a rack on the upstanding arm of the microscope and this knob engages with a plurality of short rods that slide through the bearing support plate by a turn knob and engage with a longitudinally shiftable ring having a plastic friction washer adapted more or less for engagement with a cooperating flange of the coarse adjustment gear case to thereby control the tension and permit the locking of the coarse adjustment control parts in their adjusted positions.

4 Claims, 7 Drawing Figures PATENIEDJUUOIBH 3 826 559 mnims I FBG,E

PATENTED 3.826.559

SHEEI a 0? 5 FIG.3A

PATENTED JUL 3 01974 SHEET 5 BF 5 mom mom

mm NON ADJUSTABLE TENSION CONTROL MEANS FOR MICROSCOPES THE SPECIFICATION This invention relates to microscopes and more particularly to the coarse adjustment control means therefor.

A principal object of the present invention is to provide in a microscope an adjustable tension control means fo use with a coarse adjustment mechanism to reduce the amount of play between the microscope adjusting parts so that the specimen platform cannot readily float or settle by gravity from focus with the microscope lens system once the proper focus has been established.

Another object of the invention is to provide in a microscope having a coarse adjustment, a simple turnknob arrangement that is concentrically carried by the coarse adjustment and which will effect frictional engagement between the pinion gear case of the coarse adjustment mechanism and the vertically-adjustable main block, but is operable not only to effect frictional control between the parts but also to provide a locking device by which the specimen platform can be locked against flotation for the taking of photographs of the specimen.

It is another object of the invention to provide a combination coarse and vernier control arrangement of a microscope with a frictional coarse and lock device that can be adjusted to suit the users focusing preference which has an adjustable stop means for controlling the amount of frictional control or the locking of the parts that can be effected by the friction control device.

For a better understanding of the invention, reference may be had to thefollowing detailed description taken in connection with the accompanying drawing, in which:

THE FIGURES FIG. 1 is a perspective view of binocular microscope to which the adjustable tension control of the present invention has been adapted.

FIG. 2 is a four-way exploded view in perspective of the microscope control parts for raising and lowering the specimen slide support and of the adjustable tension control parts forming a part thereof.

FIG. 3 is an enlarged sectional view taken alongline 33 of FIG. 1 and through the adjustable tension control of the microscope coaxial coarse adjustment unit with the friction parts of the tension control released from engagement with the pinion gear case.

FIG. 3A is a similar longitudinal sectional view taken generally along thesame line 33 of FIG. 1, but with the tension control parts are locked in frictional engagement with the pinion gear case with the adjusting parts and scale located at the opposite side of the microscope arm from the tension control parts being generally shown in full or fragmentation.

FIG. 4 is a transverse sectional view taken through the tension control wheel and internal parts thereof as viewed along line 4-4 of FIG. 3 when the tension control parts are free of engagement with the pinion gear case.

FIG. 4A is any enlarged transverse view taken along line 4a-4a of FIG. 3A with a tension control wheel adjusted to a position in locking engagementwith the gear case.

FIG. 5 is an enlarged exploded view of the microscope coaxial coarse adjustment unit parts and withdrawn from one side of the square metal block that supports a coarse and fine adjustment assembly and lying forwardly of the overhang portion of the upstanding microscope arm.

DETAILED DESCRIPTION OF THE INVENTION Refering now particularly to FIG. I, 20 represents a binocular microscope that comprises generally aflat bottom base 21 to which is connected anupstanding arm 22 that has an overhangsupport fitting portion 23 to which abinocular lens assembly 24 with itslens tubes 26 and 27 projecting upwardly in an inclined manner and with thelens tube 27 having a focusing knob 8 so that the user of the microscope can view with both eyes through a system of lenses and prisms provided in thebinocular assembly 24 to observe a specimen on a microscope slide indicated generally at 29 and carried upon an adjustableslide plate platform 31 and through any one of a series ofoutlet lens assemblies 32 and 33 carried by aturntable 34 on the underside of the lensassembly support portion 23 of theupstanding arm 22 that overhangs theplatform 31. The outlet lens assemblies 32 and 33 depend downwardly and laterally outwardly generally at degrees apart with three of these assemblies attached to theturntable 34, with but two lens assemblies being shown, there being usually three, and so-angled downwardly and outwardly from the underface of theturntable 34 and from the axis of theturntable 34 being angled from the axis of the lensassembly support portion 23, that one at a time the lens assemblies 32 and 33 and any other lens assembly that might desirably be used at the third location on theturntable 34 may be axially aligned with a hole36 in theplatform 31 so that the specimen carried on theslide 29 overlying the hole can be observed. Carried on thebase 21 and extending upwardly therefrom is alight device 37 that directs light rays upwardly through thehole 36 and into any one of the outlet lens assemblies 32 and 33 that may be aligned with thehole 36 in theplatform 31 wherein the specimen carried by theslide 29 may appear translucent.

Attached to the underside of theplatform 31 is an adjustable light condenser assembly through which the light rays from thelight device 37 on thebase 21 may pass before entering theopening 36 of the platform. This condenser assembly is adjustable in a manner to be described later herein.Platform 31 has a fore and aft movabletransverse beam 41 with afront plate 42 fastened thereto and which carries ajaw member 43 that extends forwardly against which one edge of thespecimen slide plate 29 is retained, with its opposite edge held in place thereagainst by a spring-biased bell-crank finger 44 that can be released by depressingupstanding handle 46 with theslide plate 29 retained between thejaw 43 and thefinger 44.Plate 42 can follow the fore and aft movement of thebeam 41 and with thefront plate 42 being in the form of an adjustable cross-slide laterally adjustable over the front face of thetransverse beam 41 and to which the finger andjaw assembly 43 is actually secured so that a transverse movement of theslide 29 thereby can be effected.

Thetransverse beam 41 has, on one side of the platform a forwardly'extending guide-way arm 47 that is worked by a rack and pinionturn knob arrangement 48 so that theguideway arm 47 can be slid along adove tail member 49 on the side of theplatform 31 fowardly until the end of theguide arm 47 may engage with an outwardly extending pin stop 51. Through an effective rack and pinion arrangement, not shown,cross slide 42 on the fore and aftmovable beam 41 can beadjusted to adjust theslide 29 carried between thejaw 43 and thefinger 44 sidewise in a desired amount and which is operated by aturn knob 52 underlying thebeamadjusting knob arrangement 48.

The dependingplatform 31 is fixedly carried on a depending bracket orstage holder 53 that is in turn adjustably carried for vertical adjustment upon the outer face of a coarse andvernier adjustment assembly 54 that is in turn adjustable on theupstanding arm 22. Thisadjustment assembly 54 has acoarse adjustment knob 55 for effecting adjustment of theassembly 54 upon thearm 22 and a vernier adjustingknob 56 for effecting the adjustment of theplatform bracket 53 coaxially arranged with the coarse adjustingknob 55. At the oppo site sideof the microscope extending outwardly from theadjusting assembly 54 areknobs 55 and 56 that work in unison with the respective knobs S and 56 and on which thevernier knob 56 has avernier scale 57 that works with reference to an arrow indication on the coarse knob 55'.

it is particularly in connection with this vernier andcoarse adjustment assembly 54 in which the present invention is incorporated in the form of a tensioncontrol wheel arrangement 58 shown in FIG. 1, lying on one side of theassembly 54 and which will be later described in detail, can be adjusted to frictionally retainplatform 31 in its adjusted position against the action of gravity when thewheel 58 is turned to effect a tightening action upon the internal parts of the coarse andvernier adjusting assembly 64. This adjustingassembly 54 and its parts are seen in the exploded view of FIG. 2 taken with the longitudinal sectional and enlarged assembly views of FIGS. 3, 3A, 4, and 4A.-A detailed description of the adjusting assembly and its parts will now be made, with particular reference to their show ing in the exploded view of FIG. 2.

Theupstanding arm 22 is rigidly secured to thebase 21 from the hollow underside of the base in any suit-v able manner that provides a rigid connection therewith at the lower end of the arm and against lateral and vertical displacement therefrom. Beneath the overhanging binocular microscope supportingarm portion 23 is a flat vertical attachingface 61 having threescrew holes 62 vertically spaced from one-another for the attachment thereto of arack guide 63 byscrews 64.

Pins 66 further connect and align theguide 63 on the surface61 by entering theholes 66 therein. Thisrack gear guide 63 is generally'of dove-tail section with oppositely inclined guide surfaces upon which slides amain metal block 67 that holds the coaxial coarse andfine adjustment assembly 54 and by which theblock 67 is vertically worked up an down upon theguide 63 and thesupport arm 22. Therack gear guide 63 is received within a vertically-extending correspondingdovetail section slot 68 on the rear face of theblock 67. Therack gear guide 63 has a vertically extending groove 69 centrally aligned on its front face within which is securedrack gear 71 by screws 72 to be carried thereby and with the screws 72 respectively entering threadedholes 73 in thegear guide 63. The front face of themetal block 67 has a'vertically -extending closedbottom slot 74 and an integral forwardly-extendingside edge 76 with a vertically-extendingslot 77 running throughout the extent of its inner face serving to carry small ball-bearingguide rods 78 between which runs a series ofball bearings 79 held captive within ballbearing support plate 81 for the connection therewith of afine adjustment slide 82 having a groove 83 confrontinggroove 77 in the blockside edge extension 76 and adapted to containside rail rods 84 in which theballs 79 will run. Top andbottom stop pins 86 and 87 are threaded into theslide 82 and engaged by the ends of the ball-support plate 81 to limit the vertical adjustment of thefine adjustment slide 82 and to holdballs 79 against vertical displacement from theirconfinement inbetween rods 78 and 84.

In the opposite side of the verticalfine adjustment slide 82 is a groove 88 that contains parallelwall guide rods 89 in which a series ofsmall ball bearings 91 travel while being contained within a ball-support plate 92 and working in spaced guide-rods 93 carried in agroove 94 of a detachable block metal guide 95 opposing theside edge extension 76 and secured on the face of the square metalmain block 67 by a series of fasteningscrews 96 enteringholes 97 in the front face of theblock 67. Top and'bottomstop pins 98 and 99 are threaded into thefine adjustment slider 82 for engagement by the ends of theball support plate 92 to confine theballs 91 between theslider 82 and detachable side block guide 95. These parts assembled upon thesquare block 67 will contain thefine adjustment slide 82 for fine vertical and vernier adjustment upon themain block 67. The upper end of theslide 82 has connected thereto for movement therewith, upon the rear face thereof and lying within the cut-away opening 74 of themain block 67, a short metal block 101 the lower end face of which has a small opening, or indentation not shown, for receiving height pin 102 carried'upon the upper edge of fineadjustment cam lever 103 pivotally attached by ascrew 104 and aspacing washer 105 to themetal block 67 within thecutaway opening 74 atcutaway edge 106 thereof so thatlower end 103 will be engaged by a face of an enlargement orflange 107 of a vernier adjustingshaft 108 that forms part of an assembly that extends through a laterally extending large opening 110 in theblock metal 67 asfine threads 109 at one side of theflange 107 that have threaded engagement within a threadedhole 111 of a main pinion gear case-part 112 that is threadedly connected by its threadedend 113 in a threadedopening 114 containing awasher 116 of a piniongear case part 117 having apartial gear formation 118 extending thereabout which has mesh with therack gear 71 when the assembly including theparts 108, 112, 117 are mounted and held within the through-opening 109 of themetal block 67 by means to be described, for rotation of thegear 118 by knobs above described for the purpose of effecting coarse adjustment of theblock 67 upon thearm 22 and the vertical adjustment of the fine adjustingslide 82 on theblock 67 by the vernier adjustingshaft 108.

Thegear case part 112 hasflange 119 that abuts the threadedopen end 113 of thegear casing part 117 and which also abuts abearing support plate 121 secured over the opening 109 byscrews 112 enteringholes 123 in the right side face of themetal block 67.

Thegear casing part 117 is somewhat similarly supported on the opposite side of the opening 109 of theblock 67 by an affixing bearingsupport plate 128 in whichgear casing part 117 is journaled along with aplastic ring washer 125 and abutting the end of a thin axially adjustingring 124 againstannular shoulder 126 ofgear casing part 117 to minimize wear and to provide frictional engagement therewith. This adjustingring 124 is contained in acircular recess 127 of thick metal bearingsupport plate 128 provided on its opposite face with a reduced diameter threadedsleeve portion 129. Thissupport plate 128 is fixed to the opposite side face ofblock 67 by fasteningscrews 131 and therecess 127 will contain therein adjustingring 124 with its oppositely extending sleeve portion 124' against the end of whichplastic friction ring 125 abuts. With theseparts 124 and 128 assembled upon theblock 67 with thescrews 131, thegear casing part 117 with the vernier adjustingshaft 108 is supported for rotation to provide for coarse and fine adjustment of theblock 67 upon theupstanding arm 22.

Within thisbearing support plate 128, there are provided threesmall holes 132 that extend into itscircular recess 127 and in which there is slidable respectively shortfriction control rods 133 enteringrecess 127 of thesupport plate 128 for frictional engagement with the inner face of the thin adjustingring 124 and serving when forced inwardly into the recess against thering 124 to provide frictional restrictive engagement therewith and of theplastic ring 125 with theshoulder 126 to thereby lock thegear case part 117 against turning movement in theblock 67 and the lowering of theblock 67 upon thearm 22 such as would be affected by gravity of the specimen platform that would put the specimen out of focus with the microscope lenses. This is the critical part of the assembly for effecting friction control locking of the parts which when used withfrictional control knob 58 threadedly connected by itsinternal threads 136 with the threadedsleeve portion 129 of the thickbearing support plate 128 and the tightening of theknob 58 thereon to force inwardly thesmall rods 133, takes-up lost motion between the thin adjustingring 124 and the thickbearing support plate 128 and makes for more or less frictional engagement with theflange 126 of thegear casing part 117 to thereby lock thegearpart 117 in effect to theblock 67 so that vertical adjustment of the block cannot be readily effected and the lowering of theblock 67 with thespecimen platform 31 thereon as by gravity and weight will not be affected, so that the focus of the microscope upon the specimen for a given adjustment will be retained. it is with these frictional control parts that the novelty of this invention lies and of which further description will be made of its operation hereinafter when the description has been completed of all of the parts of FIG. 2.

Acompression spring 137 is fitted into a bottom hole in themain metal block 67 and contained therein by aspring case 138 tightly fitted within the hole and closed at its bottom by aring 139. Thisspring case 136 is inserted in a hole in the base 21 in the top thereof up to itsflange 141. Thisspring 137 provides support for theblock 67 against ordinary downwardly displacement thereof but thespring 137 is not under such tension as to always eliminate any settling by gravity by virtue of looseness of parts that would tend to get the specimen out of focus with the microscope lens system and does not eliminate any need for the friction control device 6 of the present invention.Spring 137 merely provides cushioning action.

Twocover plates 142 and 143 are respectively secured to the upper end of theblock 67 by fastening screws 144. A stopping assembly indicated generally at 146 is provided on the upper portion of thearm 22 and supported within anindenture 147 thereat. Thisstop device 146 comprises a T-shapedblock 148 that rests over theindenture 147 and is secured to thefront face 149 thereabove by fasteningscrews 151. A roundvertical opening 152 is provided in the block in which stopplunger 153 is locked at any vertically-adjusted position within theblock 148 by a finger adjusting setscrew 154 inserted into theblock 148 and extending from the side thereof and adapted to engage with the surface of theplunger 153 to hold it at the desired vertical location against action of acompression spring 156. Ascrew 157 is inserted into the side of theplunger 153 that extends outwardly from theslot 152 for engagement with therear plate 142 fixed to theblock 67 to thereby stop the upward movement of theblock 67.

Fastened to the verniervertical slide 82 that is adjustable in theblock 67 is the dependingbracket stage holder 53 which has laterally extending supportingwing portions 162 and 163 extending from the opposite sides thereof onto which thespecimen plate platform 31 is attached by screws entering throughholes 164 and 165 thereof and up into the underface of theplatform 31. Thisstage holder 53 will move up and down with the coarse adjustment of theblock 67 and relative to theblock 67 by the fine adjustment including thecam lever 103, pin 102 that engages with the underside of the short metal block 101 which also is fastened to thevertical slide 82 by screws 82' that enter threaded holes 101 in the block 101.Screws 166 vertically spaced from one-another extend through theholes 166 in thestage holder 53 and intoholes 167 in the front face of thevertical slide 82.

A dove-tail section guide 168 is secured byscrews 169 to the front face of thestage holder 53 and within agroove 171 thereof there is fitted a gear rack 172 that is secured byscrews 173.

Acondenser supporting bracket 174 having adovetailed groove 175 is slidablymounted upon thedovetail guide 171 carried on thestage holder 53. The condenser holder carries a pinion, not shown, extending transversely within thedovetailed slot 175 and in engagement with rack 172 so that when itshand knob 176 is turned, thecondenser support 174 can be adjusted vertically upon thestage holder 53 to the desired location. Thecondenser support 174 has aring formation 177 into the underside of which can be fitted a condenser-supportingsleeve 178 with threads 179 by which thesleeve 178 is locked in place in thering formation 177 by alock ring 181 engaging thering portion 177. Thelight condenser assembly 38 in turn fitted into thecondenser sleeve 178 and will move vertically therewith upon thehand knob 176 being turned to adjust the light condenser relative to thestage holder 53 and to the underface ofplatform 31. Aset screw 182 will hold thecondenser assembly 38 locked in place within thecondenser sleeve 178 and upon thering formation 177.

Thegear casing part 112 is threaded by its threadedend portion 113 into threadedopening 114 ofgear casing part 117. Thevernier shaft 108 is threaded at and has a threaded connection with the interior of thegear casing part 112 by the threads 111 thereof. Thegear case part 112 is journaled in thering support 121 and thus can turn therein and theshaft 108 can thus turn ingear case part 112. Aplastic ring washer 186 is engageable with the. end-faceof thesupport ring 121 on theblock 67 FIG. 3 to takeup wear and this ring is enclosed in a recess in the coarseadjustment turn knob 55 that is threaded upon a threadedportion 187 of thegear case part 112 against ashoulder 188 and held. thereagainst by alock washer 189 with aset screw 191 to keep thelock nut 189 from turning from its locked position. Thus, the knob 55' can be turned as well as theknob 55 to effect rotation of the assembledgear case ports 112 and 117 and thegear 118 thereof along with other parts so that theblock 67 and theplatform 31 can be adjusted for coarse adjustment by the right hand as well as by the left hand to place the specimen in focus with the microscope lens system. On the right hand outer end of thevernier shaft 108 isthe vernier knob-56' having a cup-shapedpart 192 secured to its inner end thereto and turnabletherewith and bearing upon its periphery ameasuring scale 193 so the turning of the knob 56' will effect turning of thescale part 192.

Thisscale part 192 withscale 193 lies within the knob portion bearing an index mark orarrow 194 FIG. 2.

- Thescale part 192 may be splined as indicated-at 195 upon reduceddiameter portion 196 of theknob 56. Knob 56' is fixed against axial displacement from the outer end of thevernier shaft 108 by anend fastening screw 197 and against rotation thereover by aset screw 198.

Since thegear case part 112 is held against axial displacement, the screw threads 110 as theshaft 108 is turned, the shaft as viewed in FIG. 3 will be adjusted to the left for the purposes of working thecam lever 103 of FIG. 2 that lies in the path of movement of theflange 107 and thus effecting vernier adjustment of theslide 82 relative to theblock 67 as above described. In order to limit the axial adjustment of theshaft 108, a stop screw is provided on th outerend of thegear casing part 112 as indicated at 199 that will be engaged bystop screw 201 on the reduced diameter end of theknob 56 to thereby limit the amount of the vernier adjustment. Thegear casing 117 has a threadedexternal portion 202 On whichcoarse adjustment knob 55 is threaded against ashoulder 203 on the gear casing part l17,-theknob 55 havinginternal threads 204, FIG. 2 for this purpose. Theknob 55 is locked against theshoulder 23 by alock nut 206 that when placed in the locking position is held against rotation by aset screw 207.

Thus, when theknob 55 is turned by the left hand, thegear 118 is turned to act upon therack 71 on thearm 22 so as to cause themain block 67 to move vertically thereupon. Awasher 209 is disposed between the end of the threadedportion 129 and arecess 210 in the inner face of theknob 55 to take-up any wear therebetween.

Thevernier adjusting knob 56 is secured to theshaft 108 against axial displacement therefrom by anend screw 211 and against rotational displacement thereon by aset screw 212 so that as theknob 56 is turned by the left hand theshaft 108 will be rotated and the vernier control assembly parts will be worked. Astop screw 213 is provided on theknob 56 which will engagescrew head 214 on the end of thegear case part 117.

The arrangement and assembly of the parts ofv the microscope'should be such that there is very little play between the several parts. In FIG. 2, the vertical guide member 95 for thevertical block 67 has it'sgroove 94 deepenedto accomodate apressure groove plate 216 which is located in the bottom of thegroove 94. The parallel guide rods 93 will also lie in thegroove 94 against thepressure plate 216. Thispressure plate 216 is backed up bypressure screws 217 and 218 that are threaded into holes in the guideway member 95 for engagement with the .back face of thepressure plate 216 so that the pressure plate can force outwardly the rods 93, ball bearing-supportingplate 92 and theballs 91 to make for a more tight fitting assembly of theseballs 91 and theballs 79 to take-up any lateral play resulting from any manufacturing undue tolerances in the manufacturing of the parts or later from wear of the parts. This pressure plate means provides for an adjustment of looseness of any of the parts in the vertical vernier adjustment.

In operation, the coarse adjustment of thespecimen supporting platform 31 is effected by turning theknob 55 or theknob 55. In this manner a quick vertical adjustment and focusing of the specimen provided on theslide plate 29 is brought into focus with the binocular microscope lens system. This is effected quickly but it has been found that as a result of gravity once theplatform 31 and the specimen has been put into focus and upon leaving the microscope theplatform 31 with the specimen will have settled due to gravity and normally causing running of the parts so that upon returnjof the user to the microscope the specimen will have been put out of focus, thereby requiring a further adjustment of theknobs 55 and 55. Immediately after making a coarse adjustment of theknobs 55 or 55 in order to bring the specimen into proper focus, thevernier knob 56 or 56'is turned so that the most satisfactory and fine adjustment of the microscope lenses with relation to the specimen will have been effected. Thus, not only has a coarse adjustment been effected but also a vernier adjustment has been effected taking time of the user to prepare the microscope for the particular specimen being studied. Thus, in order that the coarse adjustment control can be locked there has been provided according to this inventionthelocking wheel knob 58 that is adjustable upon the threadedportion 129 of the bearingsupport plate 128 that is fixed by thescrews 131 to the side of themain block 67 as best viewed in FIGS. 3 and 3A. This bearingsupport plate 128 has the threeshort rods 133 slidable inholes 132 insupport plate 128 with their inner ends adapted to engage apressure plate 124 that will bring aplastic washer 125 into tight frictional engagement with aflange face 126 ofgear casing 117. Thecontrol knob 58 hasinternal thread 136 and is threaded to the threadedsleeve portion 129 of thebearing support 128 and upon being turned and engaging with the outer ends of therods 133 from a position shown in FIG. 3 so as to be moved axially along the threadedportion 129 to a position of engagement of thefriction washer 125 with theflange 126 as shown in FIG. 3A. This axial adjustment of thefriction control knob 58 is continued until astop screw 221 engages the outer face of the bearingsupport plate 128. A slight adjustment of thestop screw 221 can be made to limit the degree of friction placed upon the gearcasing flange face 126 by theplastic washer 125 and to take-up for any wear of thiswasher 125 through continued use. With thisknob 58 turned to cause thewasher 125 to have friction grip with thegear casing 117, the gear casing will thereby be automatically locked upon themain block 67 through itsbearing support 128 so that there is little opportunity for the platform supporting the specimen to lag or settle and thus the exact coarse and vernier adjustments will be maintained. Release of theknob 58 permits the user to again turnknobs 55 and 55 for further coarse and vernier adjustment.

It should now be apparent that there has been provided a friction control or lock device for use with a coarse and vernier adjustment control of a microscope that prevents the specimen and its image from floating out of focus and as well during the daily use of the microscope permit the user of the microscope to adjust the tension of the coarse control mechanism to his individual focusing preference during the daily use of the microscope. This coarse adjustment friction or lock device provides an adjustable tension control to compensate for excessive wear during continuous use of the microscope so that the specimen and its image no longer can easily float out of focus. The control device can be locked as described above in a fixed position to facilitate the taking of precise photographs with the microscope.

While various changes may be made in the detailed construction, it shall be understood that such changes shall be within the spirit and scope of the invention as defined by the appended claims.

I claim:

1. In a microscope, a base, an upstanding arm extending upwardly therefrom and overhanging the base, microscope lens assemblies fixedly mounted to the upstanding arm and a vertically-extending rack gear mounted upon the front face thereof, a main block con nected to the front face of the upstanding arm and over the rack for vertical slide adjustment with respect thereto, said main block having an opening extending laterally through the opposite side of the block, pinion gear case means extending laterally through the block opening and meshing with the arm rack and turnable to raise and lower the main block for coarse adjustment relative thereto, bearing support plates secured to the opposite sides of the main block over the laterallyextending opening and having the pinion gear case means journaled therein, a specimen slide supporting platform carried upon the front of the main block to be adjustable therewith to bring the specimen under the focus of a microscope lens assembly, a hand knob secured to the pinion gear case to turn the same, and tension control means extending between the hand knob and the gear case to regulate by friction the force required to turn the hand knob relative to the block and the lifting and lowering of the specimen slide supporting platform, said tension control means including the provision of a threaded sleeve portion extending laterally outwardly from one of the bearing support plates on the main block through which the pinion gear case extends, said one bearing support having a plurality of small holes extending through plate and parallel to the axial'axis thereof and circumferentially spaced from one another thereabout, said pinion gear case being provided with an annular radially-extending shoulder extending thereabout, friction ring means mounted on the gear case for axial adjustment thereover between the holes in the support plate and the shoulder for frictional and locking engagement therewith, short work rods respectively axially slidably adjustable in the respective small holes in the bearing support plate, and a tension control wheel threaded upon the support plate threaded sleeve portion and engageable with the short pins to apply pressure upon the ring means and the gear case shoulder when axially adjusted upon the sleeve portion toward the ring means to provide frictional or locking engagement with the gear case shoulder to thereby regulate the friction between the block and the gear case.

2. In a microscope, the combination as defined in claim 1 and said bearing support plate having a recess in its opposite face from the threaded portion thereof and said ring means being workable in the plate recess.

thereon being outwardly of the coarse control knob.

Claims (4)

1. In a microscope, a base, an upstanding arm extending upwardly therefrom and overhanging the base, microscope lens assemblies fixedly mounted to the upstanding arm and a vertically-extending rack gear mounted upon the front face thereof, a main block connected to the front face of the upstanding arm and over the rack for vertical slide adjustment with respect thereto, said main block having an opening extending laterally through the opposite side of the block, pinion gear case means extending laterally through the block opening and meshing with the arm rack and turnable to raise and lower the main block for coarse adjustment relative thereto, bearing support plates secured to the opposite sides of the main block over the laterally-extending opening and having the pinion gear case means journaled therein, a specimen slide supporting platform carried upon the front of the main block to be adjustable therewith to bring the specimen under the focus of a microscope lens assembly, a hand knob secured to the pinion gear case to turn the same, and tension control means extending between the hand knob and the gear case to regulate by friction the force required to turn the hand knob relative to the block and the lifting and lowering of the specimen slide supporting platform, said tension control means including the provision of a threaded sleeve portion extending laterally outwardly from one of the bearing support plates on the main block through which the pinion gear case extends, said one bearing support having a plurality of small holes extending through plate and parallel to the axial axis thereof and circumferentially spaced from one another thereabout, said pinion gear case being provided with an annular radially-extending shoulder extending thereabout, friction ring means mounted on the gear case for axial adjustment thereover between the holes in the support plate and the shoulder for frictional and locking engagement therewith, short work rods respectively axially slidably adjustable in the respective small holes in the bearing support plate, and a tension control wheel threaded upon the support plate threaded sleeve portion and engageable with the short pins to apply pressure upon the ring means and the gear case shoulder when axially adjusted upon the sleeve portion toward the ring means to provide frictional or locking engagement with the gear case shoulder to thereby regulate the friction between the block and the gear case.

2. In a microscope, the combination as defined in claim 1 and said bearing support plate having a recess in its opposite face from the threaded portion thereof and said ring means being workable in the plate recess.

3. In a microscope, the combination as defined in claim 1 and an adjustable stop screw carried upon the tension control wheel and engageable with the ring means to limit the axial movement of the control wheel upon the support plate threaded portion and the degree of friction upon the gear case shoulder.

4. In a microscope, the combination as defined in claim 1 and vernier control adjustment means being carried upon the main block and operable independently of the coarse control means by a shaft extending through the gear case assembly and with a knob thereon being outwardly of the coarse control knob.

Images