US1291211A - Thread-micrometer. - Google Patents

Description

J. T. SLOCOMB.

THREAD MICROMETER.

APPLICATION man JUNEH. 19 l7.

1,291,21 1., Patented Jan. 14,1919.

I mmw JOHN '1. SLOCOMB, 0F PROVIDENCE, EHOIDE ISLAND, AEBIGrhlUT-t TU ll. T. SLOCOMB CUMPANY, OF PROVIDENCE, RHOIDE ISLAND, 1-1 CORPORATION OF RHODE ISLAND.

THREAD-LWIIGROIVIETEE.

Application filed June 11, 1917.

To aZZ whom it may concern:

Be it known that T, JOHN-T. SLoooMB, a citizen of the .United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Thread-Micrometers, and T do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to micrometers, and more particularly to micrometers for measuring. the diameter of threaded work. 1 it The object of the present invention is to devise a micrometer for making accurate measurements of threaded work throughout a wide range both as to diameter and size of thread. A further object of the present invention is to improve the accuracy of thread micrometers by providing a thread-engaging anvil which has a limited rotational movement to adjust itself accurately upon the work. 7

With these and other objects in view, as will hereinafter appear, the present invention consists of the micrometerhereinafter described and more particularly defined in the claims.

In the accompanying drawings which illustrate what is now considered a preferred form of the present invention, Figure 1 is a side elevation of the micrometer; Fig. 2 is a cross section on line 2-2, Fig.1, looking in the direction of the arrows, and Figs. 3 and f are views of the anvil members detached showing their difierent lengths of stem and sizes of anvil for use upon difi'erent diameters of work and sizes of thread.

As shown in Figure 1 the micrometer comprises a substantially til-shaped frame 5having at one end a cylindrical boss 6 in which is rotatably mounted the threadedmicrometer spindle 7 having the tapered thread engaging face 8 and the usualgraduated thimble 9. v v I The opposite end of the frame is provided with a pair of cylindrical bosses 11 and 12 in axial alinement with each other and with the micrometer spindle 7. The boss 11 is provided with a cylindrical recess in which is mounted the anvil member 13 carrying a thread engaging anvil 14 on its end toward the micrometer spindle. This anvil, as well Specification of Letters Patent.

Patented Jan. 14f, rare.

Serial No. 173,9641.

shown in Fig. 1, which illustrates the memfrom time to time, as may be necessary to give true readings of the micrometer, the

frame being split as shown in Fig. 2, and a clamping screw 19 being provided for pinching the frame upon the abutment screw 18. The anvil member 13 may be clamped in fixed position in the boss 11 when the operator so desires by means of the clamping screw 21 and nut 22 having the handle 28.

In order to permit the anvil member13 to have a limited amount of rotation to adjust itself upon the work, and also to prevent the anvil member from accidental displacement a split collar 25 has been provided which may be secured by means of the clamping screw 26 upon the end of the member 13 which projects from the boss 11 toward the abutment screw 18. This collar is provided with a flat face 27 (see Fig. 2) between which and the frame at 28 there is a sufficient clearance to permit a slightrotational movement of the anvil so that it may, adjust itself upon the thread of the work, the nut 22 being at such times loosened upon the clamping screw 21 by. means of the handle 23.

When the anvil member shown in full lines in Fig. 1 is used, the micrometer is adapted to measure work only slightly less in diameter than the distance shown between the anvil 14: and thecontact face 8 of the spindle. In order to permit work of much smaller diameter to be measured, the anvil member 30 shown in Fig. 3 will be substituted, bringing the anvil then into the po sition shown in dotted outline in Fig. 1. Where the micrometer spindle is graduated infractions of an inchand has a range of movement of one inch, the anvil members will difier in length by one inch so that the workman may obtain the true dimension of the work by simply adding to the readings of the micrometer spindle the number of inches required for each. particular anvil.

"theclampin'gnut 22 is loosened, and the an- Vll memberis inserted in the recess in the "boss 11, the :end of the member passing through'the collar 25 and into engagement with the adjusting screw 18. The anvil member is then turned to bring the notch into substantial alinement with the plane of the frame, and the clamping screw 26 is tightened While "the anvil member is held in this position. The'correctness of the adjustment'oftheabutment screw 18 may be "tested by means of a standard which is placed "between the anvil and the contact face 8 on the micrometer spindle. If the mici'ometefdoesnot give the exact predet'ermined reading with this standard, the screw 19 will be 'loosenedand the abutment "strewn; adjusteduntilthe proper reading is'sciii'ed, when the clamping screw 19 is to prevent change in the adjustment.

, The micrometer will-be used in the ordinary manner,'-the notch in the anvil engaging fa thread -and the micrometer spindle being "turnedto bringthe-contact'face 8' on the inclined face of two adjacent threads with the proper'amount of pressure. Preferably 'theclampin g nut 22 will'be loose so that the an'vil "m'ay rotate slightly to adjust itself upon the work. The reading of the micrometer will then give the true diameter of the threaded "work.

While thedrawin'gs illustrate, and I have "described what is now believed to be the preferred embodiment of the present in- "vention, it"is "tobe understood that it may be embodied in various other forms and arrangements within the limitations defined in the claims.

H'avingthus-described the present invention, "what 'is cl'aimed is 1. In a micrometer, the combination with theframe provided with two axially alined :r'eces'ses, 'ofthe'mi'crometer spindle rotatably A mounted fin'onefof said recesses, an anvil member mounted for free rotation without axial movement in the other recess and provided "with "an'anv1lhav1n'g a work enga'ging notch opposite the end of the mi- 'crometerspindle, and means for limiting the extent of rotational movement of the member and anvil whereby the anvil will be held in position to engage the work and to adjust itself thereon.

2. In a micrometer, the combination with the frame, of the micrometer spindle rotatably mounted therein, and a plurality of interchangeable anvil carrying members adapted to be mounted in the frame and provided with thread-engaging anvils each having a thread-engaging notch, the size of the notch varying in the different anvils to fit difierent sizes of thread, and the anvil members being of different eli'ective lengths, the longer members having the smaller notches.

3. In a micrometer, the combination with the frame provided with a plurality of recesses, a. micrometer spindle rotatably mounted in one of said recesses, an anvil member mounted for rotation without axial movement in another of said recesses and in axial alinement with'the spindle and provided with an anvil and having a notch on its work engaging face, and a collar detachably mounted upon said member and arranged to engage the frame to limit the extent of rotational movement of the member whereby the anvil is held in position to engage the work and adjust itself thereon.

4. In a micrometer, the combination with a substantially U-shaped frame provided at one end with a pair of axially alined cylindrical bosses, an anvil member rotatably mounted in one of said bosses, an adjustable abutment screw mounted in the otherboss and engaging the end of the member, a collar secured to saidmember between the two bosses to limit the extent of rotational movement of the member, and a micrometer spindle mounted in the other end of the frame.

' 5. In a micrometer, the combination with the frame, of the micrometer spindle rotatably mounted therein, an anvil member mounted in the frame for rotation without axial movement and provided with a work engaging face shaped to fit the threads of the work, and'devices for holding the member from rotation and for permitting rotational movement in either direction and only to a limited extent, whereby the face of the anvil member will be held in position to engage the threads of the work and to adjust itself thereon, said devices being under the control of the operator.

JOHN T. SLOCOMB. 'Witnesses:

HOWELL C. SHORT, LILLIAN E. WHITTAKER.

initia or thismatentmay be obtained for five cents each, by addressing the "Commissioner of intents, Washington, D. G.

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