US3050301A - Differential gearing-actuated work holder clamp - Google Patents

Description

Aug. 21, 1962 H. PALAZZOLO 3,050,301

DIFFERENTIAL GEARING-ACTUATED WORK HOLDER CLAMP Filed Sept. 21, 1959 2 Sheets-Sheet 1 Tim MENTOR. HENRY PALAZZOLO paw-W ATTORNEYS Aug. 21, 1962 H. PALAZZOLO DIFFERENTIAL GEARING-ACTUATED WORK HOLDER CLAMP Filed Sept. 21, 1959 2 Sheets-Sheet 2 INVENTOR. HENRY PALAZ ZOLO ATTORNEYS United States Patent Ofifice 3,56,31 Patented Aug. 21, 1962 3,059,301 DIFFERENTIAL GEARING-ACTUATED WORK HOLDER CLAMP Henry Palazzolo, 1393 Fontaine Ave., Madison Heights, Mich. Filed Sept. 21, 1959, Ser. No. 841,320 6 Claims. (Cl. 269-418) This invention relates generally to the work holder art and more particularly to a novel and improved work holder which incorporates a differential gearing arrangement adapted to actuate a pair of work engaging jaws toward and away from each other so as to clamp a workpiece therebetween.

It is animportant object of the present invention to provide a work holder which may be used as a separate unit or which may be used in sets or groups and operated by suitable interconnecting driving means.

It is another object of the present invention to provide a work holder having a pair of jaws which are movable by a differential gearing arrangement and wherein the jaws are each provided with a floating work engaging-body.

It is still another object of the present invention to provide a work holder which is compact and rugged in construction, economical of manufacture and efficient in use and operation.

Other objects, features and advantages of this invention will be apparent from the following detailed description and appended claims, reference being had to the accompanying drawing forming a part of the specification wherein like reference numerals designate corresponding parts of the several views.

In the drawings:

. FIG. 1 is a central, longitudinal, elevational, sectional view of a work holder made in accordance with the principles of the invention, taken along the line 11 of FIG. 2 and looking in the direction of the arrows;

FIG. 2 is an elevational, cross-sectional view of the structure illustrated in FIG. 1 taken along the line 2--2 thereof and looking in the direction of the arrows;

FIG. 3 is a bottom plan view of the structure illustrated in FIG. 1, taken along the line 3-3 thereof and looking in the direction of the arrows;

FIG. 4 is an elevational sectional view of the structure. illustrated in FIG. 5 taken Substantially along the line 44 thereof and showing an interconnecting driving structure for operating a plurality of the work holders; and,

FIG. 5 is a broken, longitudinal, elevational, sectional view of the structure illustrated in FIG. 4 taken along the line 55 thereof and looking in the direction of the arrows.

Referring now to the drawings, in particular to FIGS. 1, 2 and 3, wherein is shown an illustrative embodiment of the invention, the numeral indicates a tubular body or housing which is open at the ends thereof and which is substantially circular in cross section. The housing 19 is open along one side thereof as indicated in FIGS. 2 and 3 by the numerals 1-1 and 12. The housing 10 is provided with the fiat surfaces '13 and 14 adjacent the opening edges 11 and 12 respectively, as shown in FIG. 2. The open ends of the housing 10 are enclosed by the end plate retainer caps 15 and 16 which are releasably secured to the housing by any suitable means as by means of the Allen screws 17 and 18, respectively.

As shown in FIG. 1, the work holder is provided with a longitudinally extended shaft which extends into the housing 10 through the opening 19 formed through the retainer cap 16. The inner end of the shaft 20 is rotatably journalled in the bearing 21 which may be of any suitable type and which is operatively mounted in the recess 22 which is formed in the inner surface of the retainer cap 15. The outer end of the shaft 20 extends outwardly of the retainer cap 16 for operative engagement with any suitable tool for turning the shaft, as more fully explained hereinafter. The shaft 20 is further journalled on the right side thereof as viewed in FIG. 1, by means of the bearing 23 which may be of any suitable type, and which is operatively mounted in the recess 24 which is formed on the inner side of the retainer cap 16.

Centrally disposed on the shaft 20 and fixedly mounted thereon by means of the Woodruff key 25 is a diiferential driver means generally indicated by the numeral 26. The differential driver :means 26 includes the hub portion 27 which is provided with the pair of integral outwardly extended stub shafts 23 and 29. Rotatably mounted on the stub shafts 28 and 29 are the bevel gears 30 and 32, respectively. The gear 30 is rotatably mounted on the stub shaft 28 by means of any suitable type of bearing 31 and the gear 32 is similarly mounted by means of the bearing 33 on the stub shaft 29. The driving bevel gears 30 and 32 are meshably and drivingly engaged with the pair of oppositely disposed driven bevel gears 34 and 35 which are integral with and carried by the sleeve shafts 36 and 37, respectively. The sleeve shafts 36 and 37 are rotatably journalled on the shaft 20 by means of any suitable bearing means as by the sleeve bearings 39.

A first externally threaded sleeve 40 is fixedly connected by any suitable means to the sleeve shaft 36 whereby the externally threaded sleeve 40 will be rotated when the bevel gear 34 is rotated, and the externally threaded sleeve 41 is fixedly connected to the sleeve shaft 37 whereby the externally threaded sleeve 41 will be rotated when the bevel gear 35 is rotated. The externally threaded sleeve 40 is provided with a right hand thread on the periphery thereof and the externally threaded sleeve 41 is provided with a left hand thread on the periphery thereof. As shown in FIG. 1, the inner ends of the externally threaded sleeves 40 and 41 are adapted to abut against the back sides of the bevel gears 34 and 35, respectively. The externally threaded sleeves 40 and 41 are retained in place against the aforementioned gears, to prevent shifting relative to the housing 10, by any suitable bearing means as by means of the roller bearing means 42 and 43, respectively.

and 49 are releasably secured to the housing 10 by means of the screws 50. It will be seen that the retainer plates 48 and 49 function to maintain the nuts 44 and in engagement with the worm gears 40 and 41 when the externally threaded sleeves are rotated.

Fixedly secured to the nut 44 is the jaw 51. The jaw V 51 may be fixedly secured to the nut 44 by any suitable means as by screws as 52. The jaw 53 is similarly secured to the nut 45 by means of the screw 54. The

jaws 51 and 53 carry the floating work engaging pads 55 and 56, respectively, and these pads are fixed to pivot ball members 57 and 58 which are pivotally mounted in the mating recesses 59 and 60, respectively, in the jaws.

As shown in FIG. 1, the shaft 20 is provided with the flange 92 to prevent the shaft from sliding to the right thereof as viewed in FIG. 1. The flange 92 may be integrally formed on the shaft 20 if desired.

In the use of the work holder of the present invention 7 it will be understood that the housing may be mounted in any desired position and on any desired machine tool by any suitable means. It will be understood that the work holder may 'be made to any desired size. !With the jaws 51 and 5?: moved apart, a workpiece may be positioned between the work engaging pads 55 and 56 and the shaft is then turned clockwise, as viewed from the right side of the structure shown in FIG. 1. The shaft 20 rotates the bevel gears 30 and 32 clockwise and these gears lock with the bevel gears 34 and 35 and carry them along in the clockwise direction as long as the pads 55 and 56 do not engage the workpiece. As soon as one or the other of the pads engages the workpiece it stops and the respective bevel gear 34 or 35 will be stationary, as for example, gear 35. The bevel gears 30 and 32 will then continue to drive the bevel gear 34 by differential action whereby the externally threaded sleeve 49 will continue to rotate and move the nut 44 inwardly towards the workpiece. When the pad 55 engages the workpiece the differential gearing means will serve as a locking means against the pads 55 and 56 to prevent them from moving backwards to release the workpiece. In order to release the workpiece the shaft 20 is merely rotated in the reverse direction. It will be understood that the shaft .20 may be hand or power operated.

The work holder of the present invention is adapted for single or plural use. That is, it may be used in sets or groups or gangs and be operated by a driving means as illustrated in FIGS. 4 and 5. FIGS. 4 and 5 illustrate the use of a pair of work holders generally indicated by the numerals 61 and 62. The drive shafts 20a and 20b of the work holders 61 and 62 are adapted to be driven by means of the driving means 63. The driving means 63 includes a differential gearing arrangement as more fully described hereinafter. The driving means 63 includes the housing 64 which is enclosed at the ends thereof by means of the end plates 65 and 66 which are secured in place by means of the Allen screws 67. The end plates 65 and 66 are provided with the hubs 68 and 69, respectively, which are adapted to carry the bearing members 70 and 71 for journalling the ends of the shafts 20a and 20b, respectively.

The housing 64 is provided with the hollow inside 72 which communicates at one end thereof with the shaft bore 73 in which is rotatably mounted the screw shaft 74 by means of the bearing members 74a and 74b. The shaft 74 is retained in the bore 73 by means of the retainer plate 75 which is secured to the housing 64 by means of the screw 76. The shaft 74 is provided with the worm threads 77 which meshably engage the ring gear 78 which carries the cage or plate 79 which is secured thereto by means of the screws 80. The plate 79 carries the two planetary bevel gears 8-1 and 82 which are rotatably mounted on the shafts 83 and 84, respectively, which are fixed to the plate 79. The gears 81 and 82 meshably engage the bevel gears 85 and 86 which are fixedly mounted on the outer ends of the work holder shafts 20a and 20b, respectively. The plate 79 is rotatably mounted on the shaft 87 which has its ends rotatably mounted in the bearings 88 and 89 which are mounted in the recesses 90 and 91 in the ends of the shafts 20a and 20b, respectively. It will be seen that when the shaft 74 is rotated, the work holder shafts 20a and 20b will be rotated in accordance with the direction of rotation of shaft 74. The differential gearing arrangement of the driving means 63 permits the driving of one of the shafts 20a or 2% when the other has stopped due to the fact that the work pads of the respective work holder have made contact with the workpiece. The other shaft will continue to drive until the work pads of the respective work holder have made contact, then they will both drive with equal pressure until the workpiece is securely clamped.

While it will be apparent that the preferred embodiments of the invention herein disclosed are well calcu- 4 lated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What I claim is:

1. A work holder of the class described, comprising: a housing; a drive shaft rotatably mounted in said housing and provided with a differential driver means; a differential gearing means having a first pair of gears rotatably connected to said differential driver means on said shaft; said differential gearing means having a second pair of gears driven by said first pair of gears; a pair of externally threaded sleeves fixedly connected to said second pair of gears in said differential gearingmeans for rotation therewith; a pair of work engaging members slidably mounted on said housing for clamping a workpiece therebetween; and, each of said externally threaded sleeves being threadably connected to one of said pair of work engaging members for moving the same.

2. A work holder of the class described, comprising: a housing; a drive shaft rotatably mounted in said housing and provided with a differential driver means; a differential gearing means having a first pair of gears rotatably connected to said differential driver means on said shaft; said differential gearing means having a second pair of gears driven by said first pair of gears; a pair of externally threaded sleeves fixedly connected to said second pair of gears in said differential gearing means for rotation therewith; a pair of work engaging member's slidably mounted on said housing for clamping a workpiece therebetween; each of said externally threaded sleeves being threadably connected to one of said pair of work engaging members for moving the same; and, each of said work engaging members being provided with a pivotally mounted work engaging pad.

3. A work holder means of the class described, comprising: a housing; a differential gearing means mounted in said housing; a drive shaft mounted in said housing and connected to said differential gearing means for driving the same; a plurality of driven shafts connected to said differential gearing means; each of said driven shafts being rotatably mounted in a housing of a work holder and provided with a differential driver means; a differential gearing means in each housing provided with a first pair of gears rotatably connected to each of said respective differential driver means on said driven shafts; each of said differential gearing means having a second pair of gears driven by said first pair of gears; a pair of work engaging members being slidably mounted on each of the work holder housings; and, a pair of externally tlneaded sleeves fixedly connected to said second pair of gears for rotation therewith in each of the work holder housings and threadably connected with the work engaging members mounted on each work holder housing.

4. A work holder of the class described, comprising: a housing having a longitudinally disposed opening along one side thereof; a pair of work engaging members slidably mounted on said housing on the outer side thereof for movement along said opening toward and away from each other for clamping a workpiece therebetween; each of said work engaging members being provided with a threaded end extended into said housing through said opening; a longitudinally disposed drive shaft rotatably mounted in said housing and having one end thereof extended outwardly of said housing; a differential gearing means in said housing having a pair of driving bevel gears and a pair of driven bevel gears meshing with said pair of driving bevel gears and driven thereby; said drive shaft being drivingly connected to said pair of driving bevel gears; an externally threaded sleeve fixedly connected to each of said driven bevel gears; and, the threaded end of each of said work engaging members meshing with and being driven by one of said externally threaded sleeves for moving the work engaging members toward and away from each other for clamping engagement with a workpiece.

5. A work holder as defined in claim 4, wherein: each of said work engaging members is provided with a work engaging pad which is carried on a pivot ball member pivotally mounted in a mating recess in each jaw.

6. A work holder of the class described, comprising: a first housing; a first differential gearing means mounted in said first housing; a primary drive shaft mounted in said first housing and being drivingly connected to said first differential gearing means for driving the same; a plurality of secondary drive shafts connected to said first differential gearing means for driving the same; each of said secondary drive shafts being rotatably mounted in a separate second housing having a longitudinally disposed opening along one side thereof; a pair of work engaging members slidably mounted on each of said second housings on the outer side thereof for movement along said opening toward and away from each other for clamping a workpiece therebetween; each of said work engaging members being provided with a threaded end extended into their respective housing through said opening; a second diiferential gearing means in each of said second housings having a pair of driving bevel gears and a pair of driven bevel gears meshing with said pair of driving bevel gears and driven thereby; each of said secondary drive shafts being drivingly connected to a respective pair of driving bevel gears; an externally threaded sleeve fixedly connected to each of said driven bevel gears; and, the threaded end of each of said work engaging members meshing with and being driven by one of said externally threaded sleeves for moving the work engaging members on each second housing toward and away from each other for clamping engagement with a workpiece.

References Cited in the file of this patent UNITED STATES PATENTS 571,187 Burton Nov. '10, 1896 663,343 Harris Dec. 4, 1900 1,616,627 Hunt Feb. 8, 1927 1,811,299 Brockhaus June 23, 1931 1,966,338 Eggimann July 10, 1934 2,401,193 Sabin May 28, 1946 2,437,399 Morgan Mar. 9, 1948 2,511,741 Schulz June 13, 1950

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