US2314480A - Calipering device - Google Patents

Description

F. P. CLARK CALIPERING DEVICE March 23, 1943.

Filed Jan. 5, 1942 2 Sheets-Sheet 1 FRANK P. CLARK- Patented Mar. 23, 1943 UNITED STATES PATENT OFFICE 2,314,480 CALIPERING DEVICE Frank P. Clark, St. Paul, Minn. Application January 5, 1942, Serial No. 425,650

Claims.

, were pre-machined, the machinist was still confronted with a difiicult task in machining or filing the key blank in order that an accurate fit was obtained so that the key would lock the gear rotatable with the shaft without play. With my method the process of fitting a key into a keyway is not only accurate, but may be accomplished with much less labor and thus a shorter period of time is required to make and fit the keys for any key-way.

By my method I have accomplished a means of eliminating the work of filing and fitting the key blank for a shaft key. To carry out my method I have provided a key-way caliper which may be readily inserted into a key-way to take accurate dimensions and thereby simplify the process of making a shaft key. My key-way caliper is constructed to correctly measure the height, taper and width of a key-way.

In carrying out my method my caliper may be adjusted by means of a series of various sized blocks which may be securely attached to the under side of my key-way caliper and which will enable the key-way caliper to measure different size key-ways. By providing a series of different size blocks I have accomplished a means wherein a single key gauge may be used to dimension numerous sizes of key-ways. Without such an additional feature it would be necessary to provide more than one key-way caliper to do the work which one key-way caliper can accomplish.

It is also an object of the present invention to provide a key-way caliper having means which are adapted to lock the caliper with an accurate dimension of the key-way slot. The locking knobs of the caliper may be provided with a series of apertures therein which provide means ofinserting a rod into the knobs to help tighten the same. i

It is a further feature of my invention to provide a means whereby the key-way caliper may be adjusted longitudinally. By providing such a means the key-way caliper may be used to take measurements for different size keys for various key-ways.

It is a further feature of the present invention to provide a key-way caliper which is adapted to measure a key-way which has been cut in from the ends of a shaft. While it has been common practice heretofore to provide pre-machined 'key blanks which had to be filed by the machinist in order that they could be fitted tightly into a'key-way, in fitting the key into a key-way which is cut in from the ends of a shaft, it is rather difiicult to accurately fit the key. By my method and with my caliper, all that is necessary is to insert the caliper into the keyway, set the caliper, lock the same by tightening the turn knobs, and then remove the caliper from the key-way, giving the machinist an accurate dimension of the key-way.

In carrying out my method I employ a jig which I have designed, to support a floating table which receives the caliper. My stationary jig is provided with means for attaching the same to a milling machine, a shaper, or to numerous other types of standard machinery now in use in machine shops. The floating table of my jig is constructed so as to be adjustable with regard to the frame of the jig and is also provided with means whereby it can be securely locked in place with regard to the frame. The floating table is also provided with a pair of locking levers which provide a means of clamping the key blank securely in place.

It is a further object of the present invention to provide a pair of adjustable jacks removably secured to the frame of the jig and which are adapted to aid in holding the floating table against chattering while the key blank is being cut. The jacks are each provided with a round bearing head and a large adjusting nut and are further provided with a projecting lug at the base end thereof which is adapted to fit into an aperture in the base of the frame of the jig to hold the jack in place. i

It is also a feature of the" present invention to provide a pair of coiled springs which are adapted to resiliently support the floating table while it is being adjusted and locked to the frame of the jig. After a dimension for a key-way has been taken by means of the caliper, the caliper is then used to adjustthe floating table in regard to the frame of the jig. The caliper is then used to set the floating table in the proper position on the frame of the jig.

In carrying out my method, the jig is attached floating table of the jig is adjusted into proper position, using the key caliper to set the floating table in working position, and when so set a key blank may be cut in accordance with the respective dimension taken by the key-way caliper. Thus my method enables a machinist to first use the key-way caliper to get the accurate dimensions for the key, and then to set the jig for holding the key blanks in proper working position, whereupon the blank may be machined to the exact dimension so that the key will fit the key-way, thus overcoming the necessity of the hand fitting of the key and the pre-machining of the same. In this manner my method saveslabor and time in fitting a key into a key-way.

For the purpose of describing my method I have illustrated certain apparatus in thedrawings:

Figure 1 illustrates a side view of my key-way caliper and a shim block for increasing the height of the caliper when desired.

Figure 2 is a plan view of the caliper.

Figure 3' is a longitudinal section on the line 3'-3'of' Figure 2.

Figure 4 is a section on the line i4' of Figure 3.

Figure 5 is a section on the line 5-5 of Figure 3.

Figure 6 is a section on the line 66 of Figure 3.

Figure '7 is a section through a shaft and a member such as a gear or other member desired to be locked to the shaft, and showing my caliper in position to measure the height of the key-way.

Figure 8 is a section on the line 8-8 of Figure 2.

Figure 9 is a perspective of an alternative form of my key-way caliper adapted to take two-Way dimensions simultaneously in a key-way or opening.

Figure 10 is a section through a shaft and member thereon, showing a key-way and my key-way caliper measuring the width of the key-way.

Figure 11 illustrates an end view of the jig used in my method which holds my caliper and also the key blank in position to be measured.

Figure 12 is a section on the line I2--I2 of Figure 11.

Figure 13 is a plan view of my jig shown in Figure 11.

Figure 14 is a side view on the line I4I4 of Figure 11.

Figure 15 is a sectional detail showing the bed of the floating table of the jig shown in Figure 11 cut away to receive a gib key blank in the jig.

Figure 16 is a section of an alternative form of a locking block for the feeler fingers ofthe caliper.

My caliper-ing device shown in the drawings to assist in carrying out my method of making shaft keys and members which are adapted to fit into an opening is illustrated in the device A which is provided with the body portion having a fiat baselike channel member III. The member ID has longitudinal side flanges II which project up from the base Ii] and between which a rear fixed block I2 is secured by the screws IS.

The rear fixed block I2 provides a journal for the rear end of the operating rod I4 which is adapted to be operated by the knob I5. The inner end of the rod I4 is threaded at I5 into the end block I"! so that when the knob I5 is rotated in one direction the block II will be drawn toward the feeler finger block I2. The feeler finger block I8 is positioned between the fixed block I2 and the locking'bl'ockv I! which is threaded to the end It of the rod I4; The finger block I8 is formed with an elongated opening I9 through which the rod I4 freely passes and by means of a pair of guide posts 20 which are secured to the base plate IE the block I8 is guided in relation to the base II) so as to move parallel to the base on the guide pins 25. Coil springs 2I rest on top of the guide pins 29 and extend into the recesses 22 in the block I8 to act to automatically urge the feeler block I8 upward away from the plate I0.

Thus when the knob I5 is turned to release the locking block I? from engagement with the block I3, the feeler block I 8 will be automatically raised by the springs 2I. A shoulder 23 is provided on the rod I4 adjacent the journal I2 which provides the shoulder means against the side of the journal I2 so that when the knob I5 is rotated to lock the block I! against the side of the block I8, the shoulder 23 will bind against the side of the journal I2, thus locking the feeler finger block IS in the desired position between the limits of its movement regulated by the slot I9.

A front feeler block similar to I8 is provided in the feeler block 25 which is urged upwardly by the coil springs 23. The feeler block 25 has an elongated passageway 21 through the same through which the hollow operating rod 28 freely passes. The rod 28 is operated by the knob 23 to rotate the same and is threaded at its inner end 30 to threadedly engage the locking block 3I which is similar in action to the block I1. A journal block 32 is secured by the screw 33 to the base plate II). The journal block 32 may be adjusted along the base plate ID, that is, into different positions by means of the series of holes 34 for the screws 33. Thus the forward feeler block 25 with its journal 32 may be set into different positions along the base plate II].

The locking blocks I! or 3| may be formed as illustrated by the alternative form of locking block 35, as shown in Figure 16. In this construction of the locking block 36, a brake liner 3? is supported on the face of the block which is adapted to bind against either of the feeler fingers It or 25. This braking or friction forming material 37 may be of any suitable nature and is adapted to bear against the side of the feeler block when the knobs I5 or 29 are operated to draw the locking block 36 tightly against the surface of the feeler block to positively lock the same. The liner 31 may be of a rubber composition, a soft metal, or like brake lining material, and in fact, may be of any suitable material to act to increase the locking grip by the block 36 to hold the feeler fingers positively in place once they are set. This construction prevents the feeler fingers I8 or 25 from moving after once they have calipered a key-way so long as the knobs I5 and 29 are operated into locking position.

The knobs I5 and 29 are provided with key receiving recesses 38 and 39, respectively, to permit the knobs to be operated by a key inserted into these recesses when it is desired, either to increase the force in looking the knobs or to operate the knobs when they are in close quarters by means of a key which slips into the recesses 38 and 39.

In carrying out my method it is desirable to use a caliper A in a key-way 40 in a shaft such as II, shown in Figure 7. The wheel or gear hub 42 in which a complemental key-way 43 is provided is in position on the shaft and the callper A is inserted in the key-ways. When the caliper A is inserted in the key- Ways 40 and 43 the feeler blocks I8 and 25 are released by the knobs I5 and 29, whereupon the springs 2| and 26 for the respective feeler blocks I8 and 25 will automatically cause the upper sharp edges of the. feeler blocks to ride up to the surface in the key-way 3 so as to accurately caliper the incline of the key-way. The base Ill of the caliper A rests on the bottom of the key-way 40 in the shaft. When the caliper has been set in the proper position in the key-ways, either the knob l or the knob 29 may be operated to lock the blocks I1 and 3| against the respective feeler blocks 18 and 25', thus locking these blocks in the position to accurately caliper the dimensions in the key-ways. By the independent operation of the knobs l5 and 29, each of the caliper feeler blocks [8 and 25 may be locked when in the desired position to caliper the opening.

It is also apparent that as many feeler blocks as may be desired may be supplied in the caliper A and a series of knobs such as 15 and 29 may be provided for locking the feeler blocks selectively. It is also apparent that the feeler blocks 18 and 25 may be locked in downward position before the caliper A is inserted in the key-Way openings to be calipered. Then after the caliper is in position, the knobs l5 and 29 can be released, thus releasing the feeler blOCkS l8 and and the springs back of the same, causing them to automatically move into position to caliper the openings by the caliper A. After the caliper has been locked it is withdrawn from the key-ways and 43 and is ready to be used as a gauge for making a key by my method.

My caliper may be set as illustrated in Figure 10, to take the dimensions of the width of a keyway 44 in a shaft 45 which is fitted to the member 46. Thus the caliper A may caliper the height of the key as well as the width.

In using my caliper A it may be desirable to build up the base H] of the same by shim blocks If! such as I have shown in Figure 1. These shim blocks may be of any thickness desired and are adapted to be attached by the screws 41 which are shown in Figure 1 in position ready to be inserted into the holes 48 shown in Figure 2..

In this manner my caliper A may be used in larger or deeper openings.

Further, my caliper may be made in the form B illustrated in Figure 9, which provides a twoway dimension caliper device with an angle iron base portion 49 which supports the feeler blocks, their journal blocks, and the locking blocks, respectively, which are virtually identical to those described as the bearing blocks l2 and 32. In the form B of my caliper, I provide a pair of feeler blocks I8, one operating from one side of the caliper and the other operating from the side directly at right angles to the other. The front pair of feeler blocks 25 operate in the same manner, and by means of the knobs l5 and 29, the respective pairs of feeler blocks I 8 and 25 may be locked in a set position when they have calipered the desired opening. With the form of caliper B, the height of the key-way and the width of the same may be taken at one time.

A caliper of this character is desirable as it saves time and is adapted to take the two-way dimensions of a recess in which a member is to be fitted and which member must accurately fit the opening calipered, such as keys and other members being fitted into an opening.

In carrying out my method after the caliper A or B has been locked with the desired dimensions for a key, it is placed in the machining jig C illustrated in Figures 11, 12 and 13. The jig C is formed with a floating table 50 which is supported on the vertical wall 5| of the frame of the jig. The jig C is formed with a base portion 52 which may be clamped by the bolts 53 or any other suitable means, to a shaper, milling machine, or other desirable machine where the key blanks may be accurately machined.

The floating table 50 is urged upwardly by the c'oil'springs 54 and is kept in close contact under spring tension of the spring 55 to the wall 5| so that no dirt or dust may enter between the inner surface of the floating table 50 and the wall 5|. Thus the floating table is free to be moved into the desired position. After the table is in the position desired, it is locked in place by the locking bolts 56. The frame of the jig C is formed with a horizontal extending flange 51, and it will be apparent that all of the sides of the frame of the jig C, as well as the floating table 50, are machined accurately so as to be of accurate dimensions and the surfaces are smoothly polished to permit the parts to be positioned as accurately as possible in place in the J g.

In carrying out my method the caliper A is placed under the flange 5! and the floating table 50 is brought up into contact with the base It] of the caliper A, as illustrated in Figure 11, and then the table 50 is locked in place by the bolts 56, setting the floating table rigidly in place. When the table 50 is set in this manner, it may be further reinforced from the bottom by the adjustable standards 58 which bear against the bottom of the table 50 and are locked in place by the nuts 59. When the jig C is set up in this manner it is ready to receive a key blank D which is adapted to be locked in place by the clamp E with the key blank D resting on the table 50 as illustrated in Figure 11.

In Figure 15 I have illustrated a sectional detail showing a gib key blank in position on the table 50 and showing the table 50 cut out to receive the head 60 of the'g'ib key.

; It will be apparent from Figure 12 that the table 59 may be adjusted to the dimensions of the caliper A so that when the table 50 of the jig is in the desired position and the key blank D is clamped in place, the key blank may be machined to the dimensions of the caliper so that when the key blank is fully machined it may be placed in the key-ways and will fit accurate in place if it has been made in accordance with the dimensions of the setting of the caliper A.

Figure 14 illustrates a side view with the key blank D in place ready for machining and the clamps E fixed to the table 55. Figure 13 illustrates a plan view of the jig C and shows the key blank D in position to be machined. An adjustable end shoulder 6! is provided at one end of the table 5!! which has an adjusting screw 62 to adjust the longitudinal position of the key blank D and to act as a shoulder at the end of the key blank to assist in holding the key longitudinally as it is machined in a direction toward the shoulder Bl. Thus the key blank is held firmly in place.

It is therefore apparent that my method of making keys by a complete machining job of the key blank is quite simple when it is carried out by means of my caliper A or B. First, the dimension of the key-way is taken by the caliper, the caliper is locked with these dimensions so that in handling the caliper the dimensions will not be changed, then the caliper is placed in the jig C and locked in position under the longitudinal flange or shoulder 51, setting the floating table of the jig in proper position, whereupon a key blank is locked in proper position on the table 50 and the whole jig is positioned in a shaper, milling machine or other similar machine adapted-to operate to machine the key blank D accurately. In this manner, keys may be made for shafts or a member may be accurately made to fit a certain size opening without requiring filing and fitting as has usually been the case in former methods. If the key blanks are'properly machined to the dimensions of the caliper A, they will fit the key-way without further machining or finishing. I have found that this method is very desirable as it is more economical, more accurate, and much faster than the old method.

The caliper B when used to take two dimensions of an opening can be first clamped in the jig C in position to permit the machining of the key or member in one direction, and then after the blank is machined to the first dimension the caliper B can be clamped in the jig for the other dimension. and then the blank can be machined to this last dimension. Thus two dimensions of a key-way or other opening may be taken at one time by the alternative form of caliper B and the member or key blank can be finished while clamped in the jig C with these dimensions. Then, when the blank is in finished form it is ready to fit the opening for which it is intended without further machining, filing or fitting.

In accordance with the patent statutes, I have described the principles of operation of my calipering device and the method of making shaft keys, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that this is only illustrative of a means of carrying out my invention and that obvious changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim 1. A caliper for shaft key-ways comprising an elongated base member, pairs of blocks mounted at spaced positions on said base member, feelers floatingly held between the blocks of each pair and spring-pressed to an outward position, whereby the caliper may be inserted in a keyway closed at one end and the feelers will automatically position themselves to contact a wall of said key-way, and means for locking said feelers in their automatically adjusted position.

2. A caliper for shaft key-Ways comprising an elongated base member, pairs of blocks mounted at spaced positions on said base member, feelers floatingly held between the blocks of each pair and spring-pressed to an outward position,

whereby the caliper may be inserted in a key way closed at one end and the feelers will automatically position themselves to contact a wall of said key-way, and means for. locking. said feelers in their automatically adjusted position, said means including an operating member for each pair of blocks extending beyond said base member at the end of the caliper opposite that end which is inserted in the key-way.

3. A caliper for shaft key-ways comprising an elongated base member, pairs of blocks mounted at spacedpositions on said base member, one of each pair being fixed thereto and the other being slidable thereon, feelers fioatingly held between the blocks of each pair and spring-pressed to an outward position, whereby the caliper may be inserted in a key-way closed at one end and the feelers will automatically position themselves to contact a Wall of said key-way, and means extending beyond one end of the basemember for sliding the slidable block of each pair to lock the feelers in their automatically adjusted position.

4. A caliper for shaft key-ways comprising an elongated base member, pairs of blocks mounted at spaced positions on said base member, one of eachpair being fixed thereto and the other being slidable thereon, feelers fioatingly held between the blocks of each pair and spring-pressed to an outward position, whereby the caliper may be inserted in a key-way closed at one end and 'the feelers will automatically position themshaft and the second of said fixed blocks and threaded into the second slidable block whereby the feelers may be clamped between the blocks of each pair in their automatically adjusted position.

5. A caliper for shaft key-ways comprising an elongated base member, pairs of blocks mounted at spaced positions on said base member, feelers floatingly held between the blocks of each pair and spring-pressed to an outward position whereby the caliper may be inserted in a key-way closed at one end and the feelers will automatically position themselves to contact a wall of said key-way, means-holding the blocks on the base member so that said blocks may be adjusted longitudinally of the base member, and means for locking said feelers in their automatically adjusted position.

FRANK P. CLARK.

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