Dec. M), 194,6, P. A. SHAFFER, JR MICROBURET ` 2,412,295 Filed Aug. '7, 1944 INVENIOA PML/P A Smyrne-@Ä Patented Dec. 10, ' 2,412,295 UNITED ‘ «STATES ` - 2,412,295 PATENT] ` " " ' >>Mlcltonvltrz'r y . . Pump ‘ California A. snuffel-Jr., Institute nsadenacaungassignerio Research « Foundation.`` I Pasadena, Calif.,y a corporation of ` " lApplicatie”. August v_, 1944, sesamo. 548,323 10mm. `(c1.222---26>"_ , vl ‘ - eler member. I I. is provided inßtheformpr arela. tively long cylindrical nut., Near‘fit's uppertend it is provided with atransverseslity-IZ whichfis ladapted vto be compressed bya tension‘screwïlß My invention relates `to microburets vand among the objects of my invention are: First, to provide a microburet which makes pos sible accurate measurement of liquids used'in titration procedures and is particularly adapted so that slack due to the thread clearance‘between the traveler member II kand drive `s_crewß vmay for use in conjunction with the analysis of ex be taken up. In addition, the traveler Vis provided with one or more longitudinal slits„I4 ltojform tremely small samples such as used in micro chemical procedures. ' ~_ ` segmental portions which may be spreadslightly " changeably receives and operates glass syringes 10 so that the traveler member I I hasnoininal fric tional engagement with the walls of ythebarrel ' I. containing the various liquids used for titration. One side of the barrel I isk provided with Aa Third, to provide a microburet which, though` longitudinal slot I5. A lateral stem I6 yissefcilred accurately controlling the movement of the in the .traveler member II and protrudes through plunger into the cylinder of a glass syringe. places Second, to provide a. microburet which inter no side thrust on .the plunger so that the plunger 15 the slot I5. The lateral stem'fits into a socket formed 1n slide bracket I1. The end of „the slide bracket adjacent the barrel |` is curved intof'vcon formity therewith and the slideA bracket' is secured pact and easily operated. ` to the stem I6 by a set screw IBL", One vertical With the above and other objects in view which of the slide ìbracket I'I is 'inscribed with a‘ `may appear hereinafter, reference ,fis directed to 20 side reference marking which coacts witha microm the accompanying drawing in which: eter scale disposed longitudinally on the barrel I. Figure 1 is a front view of the microburet show Theunder »side of the slide bracketfisprovided ing a syringe in position. Y y moves freely. Fourth, .to provide a microburet which is com f‘Figure 2 isa side elevational view of the micro buret. with a ball bearing I9 in order vto `form"afheini 25 spherical projection. This bears against >tl‘ieph'ead Í/ ` ` P-I of a plunger P forming part of a syringes. Figure 3 is a fragmentary longitudinal sectional vThe upper corners of the vslide"bracket `are view thereoi taken through 3-3 of Figure 1. notched along the` sides of kthe bracket .tofiorm Figure 4 is a top view of themicroburet. Figurev5 is a transverse sectionalview `thereof 30 shelves on which are mounted the leverV armsil) ' of retainer clips 2 I. The lever arms ‘are vj’o‘urrialed taken through 5_5 of Figure 2 with the slide at their endsy adjacent the barrel kIjjbyf screws. bracket removed. Figure 6 is a transverse sectional view .through 8_6 of Figure 2 showing the barrel and under side of the travelerÍ member. y Figure 'I is «a transverse sectional view through 'I--l of Figure 3. ’ ` The forward vextremities of .theglever arms-are provided ¿with rudimentary yhandle lugs( .23.;11De pending arms 24 extend downward frfmigthfev lever arms 20 `and are providedwith> inturnedv extrem ities 25 which fitundery they head kP-«I ofthe plunger F. The retainer clips _2| areslightly flex 'A tubular barrel I is closed at its lower end by ible but are strong enough 'to rsisethe'plunger' in ’ a. plug 2. The upper end of the barrel I receives ball bearings aand 4. y The lower ball ybearing 3 cylindertoCthe of the "lower syringe»` side portion l, »1 ,l , „of the barrel rests on a shoulder 5 Within the barrel. A bush 40 theSecured ing B screw threads into the upper end of the I is a V-block 2B.` The V-block is providedlwith barrel I and engages the upper bearing -4.` a V-shaped groove adapted .toz accommodate -the The bearings 3 and 4 ñt the stem portion ‘I of cylinder of the'syringe and alìnerit `withthe .ball a drive screw 8. The lower bearing is press fitted bearing I9. Clamp arms 21` formed fof spring on the stem portion 'I'and _abuts a shoulder 9. Slight clearance is provided between the inner race of .the bearing 4 and the stem portion. The ` upper end of the stem portion receives a head or knob I0 for the purpose of rotating the drive screw. The head I0 includes a cylindrical por tion bearing a micrometer scale which coacts with a. reference line inscribed on lthe barrel I at its upper end. The tubular barrel I forms a guide means which receives a traveler member II. The trav 55 material are secured to the Sides'ofthebarrel I and extend laterally- along ` .the sides 'y "on/fthe V-block. vTheir extremitlesfare inturned to gripl the cylinder C and hold itinthe yV-groovebf‘f'l'wo pairs of clamp yarms’ are provided'. y¿The V-block and clamp arms thus form a holder for the'cyl- » inder C of the syringe. Each pair of clamp arms is connected by a screw 28 which extends through a hole formed in the V-block 26. One end of each screw is riveted or otherwise secured to one 2,412,995 3 tended end of each screw receives a nut 29. 4 member; a syringe plunger engaging bracket con nected to said screw member; a syringe cylinder of .thepair of clamp arms and the other or >ex . ‘» f holder attached to said guide member; and scale 'I‘he upper end of the cylinder Cv is> provided with a ñange C-I which rests against .the upper means for measuring »the extent of movement of end of the V-block so that when the cylinder is said traveler andsyringe plunger. ' ‘ 4. The> combination with a syringe having a clamped it remains in place as the plunger is - cylinderv 'and plunger, -of a microburet compris moved downwardly therein. The clamp arrns` 21' are suillciently stifl' to hold the cylinder against ing: a tubular guide member; a traveler member guided within said. guide member; a screw mem upward movement when the plunger. is with- ._ l0 -ber for moving said traveler member; a syringe drawn. The barrel'is provided with a mounting stem V30y , . plunger engaging bracket connected to’said screw -member; a syringe cylinder holder attached to by. which the microburet may be lsecured in a » suitable fitting cammed by a'ring stand or ’similarI \ ' .sugport customarily used for chemical apparatus. ‘ saidV guide member; and scale means for measur ing the extent o1' movement of said traveler and Byîreason of the micrometer scales provided" on syringe plunger..l '~ ' ' . 5. In a microburet for metering discharge o! the" head lo anden .the barrel l the extent of. , fluid from a glasssyringe wherein the syringe movement of the plunger in its cylinder kmay be The ball bearing and spring clip engagement'v includes a cylinder and Yplunger therefor, having a head at its extended end, the combination of: bind inthe cylinder dueto the snug‘iluid type. , barrel; asliding bracket secured to the protrud accurately determined. ‘ v between the slide bracket Hand the plunger P\ 20 a tubularbarreha drive screw rotatably mounted in said barrel; atraveler for said drive screw avoids the application of *side thrustv on the equipped with a lateral projection, there being plunger. This is highly desirable for leven a any `accommodating longitudinaljslotk in said moderate sidevthrust will cause .the plunger to tit which is maintained between these two mem 25 ing end of said projection; a V-blo'ck’securedto ‘ bers. " ' said barrelbelow said sliding bracket; yieldable A clamp elements on opposite sides of >'sind V`-block. The syringe per se is conventional and inas for holding the cylinder of a syringe,v against said much as they are lreadily inserted and-removed from .the V-block and slidel bracket several»- , V-block; and yieldable clips pivotally mounted on - syringes containing different liquids used- in 30 said sliding bracket and having arms" adapted 4to . `engage the >head of said plunger, wherebyjm'o've titration procedures may be used interchange ment of said _sliding bracket correspondingly ably, and 1the syringes may be inserted and re moved s'everal times as needed before their con tents are discharged. » . " r moves said plunger in saidcylinder. _ f ` ' ‘ ‘ - y6. In a microburet for metering discharge of iluid from'a glass syringe wherein the syringe'in cludes a cylinder and plunger therefor, having a head at its extended end, the combination of: a .tubular barrel; a drive screw- rotatably. mounted „ in said fbarrelya travelergfor said drive screw 40 equipped with a lateral `projection,'there being' an I claim: . . 111A microburet comprising: a'syringe includ- j accommodating longitudinal slot in said barrel; a sliding bracket secured tothe protruding end of ing'a cylinder and a plunger movable therein and said projection; a pairl of clips pivotally mounted ' provided with a head at its outer end; a tubular The various changes and altem-ate arrange ments may be made within the scope of the ap pended claims, in which it is my intention to claim all novelty inherent in the invention as broadly as the prior art permits. member having a slot in its side wall; a syringe - - on said bracket and having arms "adapted to engage the head of said syringe and hold said cylinder mounting means on said tubular member head against the under side of said bracket; and means for clamping they cylinder of said ysyringe to the side of said barrel in alinement with said below said slot for positioning said syringe cyl inder in .offset parallel relation to said tubular member; a micrometer screw »journaled within plunger. said .tubular member; a traveler member threaded l on said screw within said tubular member; -and . ' a syringe plunger engaging bracket disposedA ex ternailyoi said tubular member and attached to said traveler member through said slot. 2. The combination with asyringe’cylìrider and plunger of a microburetk comprising: va, traveler ' ,y _ " j, l head at its extended end, the combination fof: . a tubularbarrel; a drive screw rotatably mounted guide member; means secured onv said guide mem ber for removably receiving a syringe cylinder; a traveler slidable on said guide member and in cluding means for gripping the head' o1' a syringe plunger; a screw for moving said traveler; a first 60 micrometer scale incorporated with said screw and guide member; and a second micrometer scale incorporated with saidtraveler and guide i 7. In a _microburet for metering discharge'fof iiuidyfrom a glass syringe wherein the syringe in cludes a cylinder and plunger therefor, having a in said barrel; a traveler for said Vdrive screw equipped with a »lateral projection, vthere being an accommodating longitudinal y.slot in said barrel; a sliding bracket secured .to therprotrud ing end of said projection; .a pair of clips pivotally mounted on said bracket and having arms adapted to engage the headof said’syringeand hold >said head against the u-nder side of said bracket; means for clamping the cylinder of saidbsyringe member, whereby movement of said traveler and I to lthe side of said barrel in alinementîlith said syringe plunger maybe measured. 65 plunger; a handle for said drive screw mounted 3. The combination with a _syringe having a cylinder and plunger, of a microburet compris lng: a guide member; a traveler member guided thereby; a screw member for moving vsaid traveler - at one end of said barrel; and micrometer scales _ / for measuring movement of4 said handle and'said sliding bracket relative to said barrel. ._ _Y , PHILIP A. sHAFFEnun.