US2467499A - Micrometer - Google Patents

Description

Ap 1949- R. H. SACHTLEBER 2,467,499

MICROMETER Filed March 6, 1946 7 z 2e 33 24 21 9 3+ 3| 0 36 Fig 9 F 8 INVENTOB ATTORNEY Patented Apr. 19, 1949 UNI ED STATES PATENT OFFICE 3 Claims.

This: invention relates to micrometer gauges andia'naobject of the present invention is to pro vide a=microimeter which is easier to manufacture than standard micrometers of approved type, and onerwhich will have long life without impairment of its accuracy in that its movable work engaging parts will be subject to less wear than is hadin micrometers of present day approved construction.

Another object: of the invention'is to provide amicrometer which is easy to read, one in which the:spindle.may be quickly moved to the Work tovbemeasured, and-one in which the worle engaging spindle does. not turn during the final settingthereby reducing'wear on the spindle and providing more accurate measurements.

With-these and other objects in view, as may appear f-rom'the accompanying specification, the invention consists of various fea'tures'of construction'and combination of parts, which will befirstdescribed" in connection with the accompanying drawings, showing a micrometer of a preferred form embodying the invention; and'the'features forming-the invention will be specifically pointed out in the claims.

In the drawings- Figure l-is'a top plan of the improved micrometer.

Figure-'2. is a side elevation of the micrometer. Figure=.-3.-is an end view of. the micrometer.

Figures-4 is a longitudinal section through themicrometer'taken on the line 4-dof Figure'l.

Figured is a cross-section taken on the line 5-5 of Figure 4.

Figure 6 is. a fragmentary vertical section through the micrometer taken substantially on the line 6-4 of Figure 1.

Eigureflisa section takenon the line 7-'l'of Figure 6.

Figure 8 is a plan View of a friction member employed ina micrometer structure;

Figure"9 is a section on the line 99 of Fig ure18.

Referring more particularly to the drawings the improved. micrometer includesa body I having 2. depending accurate saddle or anvil carrying member 2 formed thereon to which the micrometer anvi1i3 is attached in any. suitable manner. Afispindle 4 isadjustably'carried by the body 5 and its Work engaging surface 5 co-operates with the work engaging surface of the anvil 3 to measure work.

The spindle 4 has a portion of its outer surface externally screw threaded as shown at 5 with the indicia carried portion 1 and the operating portion 8 formed at the outer ends. The threaded portion 5- of the spindle 4 is threadably engaged: inthe internal screw threads of thesleeve 9 and a knurled head. It) iscarried by the operating-l end 8 of thespindle i for rotating the spindleto cause movement thereof longitudinally of the sleeve 9; The sleeve 9 has external threads H on its outer. surface which co-operate with. the. internal threads l2 in a sleeve l3. The sleeve.|3-- is carriedby the body l and is adjustably conenected thereto by means of a threaded 00131166? tion Manda lock-nut structure l5. This'adjuste able connection betweenthe body l and the sleeve ld will permit adjustment of the-spindle 4with: respect tothe relativeportions of the sleeve 13;. sleeve 9 and-anvil il to compensate for wear.

The threadson the outside of the sleeve 9:a-re'- larger and less in. number per inch, than-are: the internal threads-or the threads on the inside of the sleeve 9. relationof twenty (20) threads per inch-on'thef; outside of the sleeve 9 and twenty-five- (25): threads per inch on the inside of the sleever9; or in' any other. suitable relation" to eachother to provide the desired differences in speed; oft longitudinal movement of the spindle by its'rota-e tion or: by the rotation of the thimble [6.

The sleeve 9 is connected to the thimble: 16: by a setscrew. l1 and the thimble lli'which: is in the-formofa sleeve-likeshell has graduationsa E8 on its tapered inner-end I9 which co-operatg:

with longitudinally extending graduations 20: formed on the outer surface of the body l. sleeve 9 which is the internal and external threaded'sleeve is connected to a rotating sleeve 2! by a'set-screw or dog-point screw Hand this:

rotatingrsleeveZ-l, bymeans of whichthersleeve; 9- is rotated is connect'ed to'the thimble lfiaby" a friction clutch-structure generically indicated:

at 23', in-Eigure 4= of'the'drawings. The friction:

clutch structure-23- comprises a friction disc or ring -24-which engages the outer end of the thimbler lt and'has a spring ring 25 cOnnected theret'or by rivets. 26. has'pins 2T carried thereby which pins'enga'ge in-openings'28 in thei'internal flange 29 formed: The" friction clutch structure These threads may'be in*the"- The springring 25' is bowed and? 30. The locking plunger or key 30 is spring pressed by means of a spring 31 and it is carried by the anvil carrying saddle or member 2 as clearly shown in Figures 6 and '7 of the drawings. A locking pin 32 is provided for locking the plunger 30 in inoperative position out of the key- Way 28. The locking pin 32 is slidably carried by the saddle 2 and moves into and out of a groove 33 formed in the plunger 30. The movement of the locking pin 32 is limited by means of the pin 34 which rides in the slot 35 formed in the locking pin. The locking pin 32 may have an operating head or lip 36 formed on its outer end.

In operation, when any piece of work is to be measured the work engaging end of the spindle 4 is moved inwardly away from the anvil 3 so that the piece of work to be measured may be positioned between the spindle 4 and the anvil 3. During this time the locking plunger 30 is held out of the key-way 28 by the locking pin 32. The spindle is then moved forward by its rotation until it touches the work to be measured at which time the locking pin 32 is moved out of locked position relative to the plunger 30 and the plunger 30 then moves into the key-way by action of the spring 31. In the event that the plunger 30 and key-way are not in proper position for interengagement, the spindle is turned in reverse or left hand direction for a part of a turn or until the key or locking plunger 30 passes into the key-way 28. The spindle is thus locked against rotary movement but is free to move longitudinally through the body I, thus the spindle is moved against the work in close relation thereto for measuring the work. The accurate measurement of the work in thousandths of an inch is provided by the movement of the spindle finally against the work through the rotation of the thimble l6 by means of the sleeve 2! which gives the final accurate movement of the spindle. The friction clutch structure 23 is tensioned so as to prevent too tight a pressure between the spindle and the work. The thickness or diameter of the work being measured is then read on the scale 1 plus the scales l8 and 20 which will give the accurate reading of the thickness or diameter of the work in thousandths of an inch.

It will be understood that the invention is not to be limited to specific construction or arrangement of parts shown, but that they may be widely modified within the invention defined by the claims.

What is claimed is:

1. In a micrometer, a body having a stationary work engaging anvil thereon, a spindle extending through said body, and havin one end thereof co-operating with said anvil for measuring work, threads on said spindle for a portion of its length, a sleeve provided with internal threads and external threads, said external threads being larger and less in number to the inch than said internal threads, the threads on said spindle engaging said internal threads, a thimble rotatable independently of said spindle and co-acting with said external threads, means connecting said thimble to said sleeve for rotating the sleeve upon rotation of the thimble, a second internally threaded sleeve co-operating with said external 4 thread for moving the thimble and said first named sleeve longitudinally upon rotation of the thimble, and means adjustable on said second sleeve for adjusting the position of said spindle to compensate for wear on the anvil.

2. In a micrometer, a body having a stationary work engaging anvil thereon, a spindle extending through said body and having one end thereof co-operating with said anvil for measuring work, threads on said spindle for a portion of its length, a sleeve provided with internal threads and external threads, said external threads being larger and less in number to the inch than said internal threads, the threads on said spindle engaging said internal threads, a thimble rotatable independently of said spindle and co-acting with said ex ternal threads, means connecting said thimble to said sleeve for rotating the sleeve upon rotation of the thimble, a second internally threaded sleeve co-operating with said external thread for moving the thimble and said first named sleeve longitudinally upon rotation of the thimble, means adjustable on said second sleeve for adjusting the position of said spindle to compensate for wear on the anvil, and locking means for locking said spindle against rotation at predetermined times whereby said spindle will move longitudinally but not rotate upon combined rotary and longitudinal movement of said thimble.

3. In a micrometer, a body having a stationary work engaging anvil thereon, a spindle extend ing through said body and having one end thereof co-operating with said anvil for measuring work, threads on said spindle for a portion of its length,

a sleeve provided with internal threads and external threads, said external threads being larger and less in number to the inch than said internal threads on said spindle engaging said internal threads, a thimble rotatable independently of said spindle and co-acting with said external threads,

means connecting said thimble to said sleeve for rotating the sleeve upon rotation of the thimble, a second internally threaded sleeve co-operating with said external thread for moving the thimble and said first named sleeve longitudinally upon rotation of the thimble, means adjustable on said second sleeve for adjusting the position of said spindle to compensate for wear on the anvil, said spindle provided with a longitudinally extending key-way, a spring pressed locking key carried by said body for engagement with said spindle to hold the spindle against rotation, and a locking plunger for holding said key out of engagement 1 with said spindle.

RUDOLPH H. SACHTLEBER.

REFERENCES CITED The following references are of record in the file of this patent:

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