US1100528A

US1100528A - Machine for grinding hobs, milling-cutters, and the like.

Info

Publication number: US1100528A
Application number: US79405113A
Authority: US
Inventors: Percy Brown; Francis John Bostock
Original assignee: Individual
Current assignee: Individual
Priority date: 1913-10-08
Filing date: 1913-10-08
Publication date: 1914-06-16
Anticipated expiration: 1931-06-16

Description

1 P. BROWN & P. J. BOSTOGK. MACHINE FOR GRINDING HOBS, MILLING GUTTERS, AND THE LIKE.

APPLICATION FILED 00T.8, 1913.

1,100,528, Patented June 16, 1914.

3 SHEETS-SHEET 1.

P. BROWN & F. I. BOSTOCK. MACHINE FOR GRINDING HOBS, MILLING GUTTERS, AND THE LIKE.

APPLICATION FILED coma, 1913.

1,100,528, Patented June 16,1914.

3 SHEETS-SHEET 2.

P. BROWN & F. J. BOSTOOK. MACHINE FOR GRINDING HOBS, MILLING GUTTERS, AND THE LIKE.

APPLICATION FILED 0OT.8, 1913.

1,100,528, Patented June 16,1914.

3 SHEETSSHEET 3.

PERCY BROWN AND FRANCIS JOHN BOSTOCK, F HUDDERSFIELD, ENGLAND.

MACHINE FOB GRINDING HOBS MILLING-CUTTERS, AND THE LIKE.

Specification of Letters Patent.

Patented June 16, 1914.

Application filed October 8, 1913. Serial is. 794,051.

To all whom it may concern:

Be it known that we, PERCY BROWN and FRANCIS JOHN BOSTOCK, subjects of King George V of Great Britain, residing at I-Iuddersfield, in the county of York, England, have invented certain new and useful Improvements in Machines for Grinding Hobs, Milling-Cutters, and the like, of which the following is a specification.

Our invention relates to machines for grinding'hobbing cutters, or milling and the like cutters and has for its object to provide an improved and simplified construction of machine for the purpose.

In describing our invention we shall refer to the accompanying drawings in which- Figure 1 is a rear elevation of a machine constructed according to and embodying the invention; Fig. 2 is an elevation looking in the direction of the arrow A, Fig. 1; Fig. 3 is a partial plan View of the machine; Fig. 4-is a detail, on an enlarged scale, of the abrasive wheel head; Fig. 5 is a section on the line BB, Fig. 4, and Figs. 6 and 7 are detail sections illustrating the dividing mechanism for the cutter supporting spindle.

Referring to the drawings, our improved machine comprises a suitable standard or frame 1 havinga guide 2 on which is vertically movable a slide 3. A cross slide 4, Fig. 2, operated by screw 5 and hand wheel (3, carries a universal head 7 supporting the abrasive wheel 8 which has its upper side or face profiled to suit the tooth to be ground. A lateral extension 9 on the standard 1 supports a dished table 10 having a central boss 11 forming a bearing for a Vertical sleeve 12, Fig. 6, in which the hob or cutter supporting spindle 13 is carried.

The slide 3 has pivotally connected to "it one end of a link 14 whose opposite end is pivotally mounted on a pin or stu 15 ad justably secured in a slot 16 in a rotatably mounted disk 17. Integral with or attached to the disk 17 is aspur wheel 18 which is adapted to be engaged and driven by a pinion 19 carried by a lever 20. A pulley 21 fast on the axis of the pinion 19, and driven by belt from any convenient source, serves to impart motion to the pinion. The lever 20.1is pivotally mounted at 22 and a spring 23 acting on said lever on the opposite side of the pivot center to the pinion 19 acts' to maintain the pinion normally in mesh with the gear 18, an adjustable stop 24 being provided to engage the lever and limit the upward movement of the pinion. The front end of the lever is provided with a foot plate or pedal 25, pressure on which causes the'lever to be rocked against the action of the spring 23 and to withdraw the pinion 19 from engagement with the gear 20. So long as the pinion 19 and gear 20 remain in mesh the slide 3 is reciprocated and a vertical reciprocatory motion is imparted to the abrasive wheel 8, and on the withdrawal of the pinion 19 the slide ceases to be driven. It is advantageous that the slide be brought to rest when desired with the abrasive wheel in a certain position, that is to say clear of the hob or cutter and to this end the lever 20 is provided with a block 26 which. is adapted, on the lever being rocked to withdraw the pinion 19, to engage the periphery of the disk 17 and to enter a recess 27 therein.

The head carrying the abrasive wheel comprises a dished casting 28 mounted to swivel on the end of the cross slide 4. A carrier 29, supported in an opening 'in a boss 30 on the casting-28 is provided with ball and thrust bearings 31 to support a spindle 32 on which the abrasive wheel 8 is secured. The carrier 29 is slidable up or down in an opening in the boss 30 to adjust the height of the abrasive wheel. The upper end of the spindle 32 carries a pulley 33, to which motion is transmitted, from a driven overhead pulley not shown mounted on a counter-balanced arm, by a cord or belt which passes between and is guided by guido pulleys34 and 35 carried by an arm or extension 36 on or secured to the upper end of the carrier 29. ..The boss 30 is split at 37 to enable the carrier to be gripped in the desiredposition by means of stud 38. The

I abrasive wheel 8 can thus be caused to occupy, and be driven in any desired position while being at the same time raised and lowered; i.

In the case of a hob, or of a milling cutter in which the face of the tooth to be ground is spiral in form, rotation of the hob or cutter to give the desired lead is effected as follows:The slide 3 has formed upon it a vertical rack 39, Fig. 3, which meshes with a pinion 40 fast on a shaft 41. suitably supported in

bearings

42, 42. Fast on one end of the shaft 41 is a gear 43r.which meshes,

through

change gears

44 and 45, with a gear 46-fast on a shaft 47 supported in suitable hearings in the frame'beneath the table 10. I the weight of theslide 3 and the parts car- Through indexing or dividing mechanism, which will be described later, motion is conveyed from the shaft 47 to a spiral gear 48 fast on the sleeve 12 which carries the hob or cutter supporting spindle 13. As the slide 3 causes the abrasive wheel to move up and down, therefore, the hob is rotated first in a forward direction and then in a backward direction, the desired lead being effected by the

change gears

44 and 45.

The indexing of the hob or cutter or the presentation of a fresh tooth thereof to the *abrasive wheel when one tooth has been ground is effected as follows :The shaft 47 has fast upon it a peripherally notched disk 49, one or other of the notches of which is adapted to be engaged by a spring plunger 50 carried by a casing 51. Mounted on a spindle in the casing is a worm 52 which meshes with a worm wheel 53 fast on a sleeve 54 on which is formed or secured a spiral gear 55 meshing with the gear 48 on the sleeve 12. On withdrawal of the plunger 50 clear of the disk 49 the casing 51 can be rotated by means of handle 56 to the extent of as many notches as may be required, the rotation of the casing, as

will be understood, causing the hob or cutter spindle, through the sleeve 54,

gears

55 and 48 and sleeve 12, to be rotated through the desired portion of a revolution to present a new tooth of the hob opposite the abrasive wheel. Independently, rotation of the worm 52, which can be effected by means of a lever or handle 57 on its spindle, enables a fine adjustment to be given to the hob relatively to the abrasive wheel to determine the depth of cut.

The disk 17 which is rotated in the direction of the arrow C, Fig. 1, has its center offset from'the line of movement of the slide 3, the effect of which is to cause a slow upward or cutting movement of the slide and consequently of the abrasive wheel, and a quick downward or idle movement.-

Since, by means of the rack 39, and the intermediate gearing, the slide 3 effects the backward and forward rotation of the hob or cutter, it follows that the speed at which the said hob or cutter is' rotated will vary with the speed of the slide, and the correct relative speeds of the hob or cutter and of .the abrasive wheel be always maintained.

The connection between the link 14 and the sleeve 3 is through a block 58 which is adjustably secured in a slot, not shown, in the slide, to enable the timing of the stroke of the slide to be adjusted.

For a hob or cutter whose teeth form left handed spirals the abrasive wheel would be reversed.

A pulley 59 fast 'on the shaft 41 has connected to its periphery a chain or the like 60 supporting a weight 61 to counter-balance ried thereby.

The machine can be advantageously employed for grinding ordinary milling and like cutters in which case one of the

gears

43 or 44 would be removed or slid out of mesh to allow the spindle 13 to remain stationary instead of rotating forward and backward as above set forth.

An opening 62 in the table 10 permits the lubricating water employed to drain away through suitable passages, not shown, to a combined tank and pump (53 from whence it is returned to the hob.

The vertical arrangement of the hob or cutter spindle as herein set forth presents many advantages of a practical nature over the horizontal arrangement hitherto adopted.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is 1. In a grinding machine, the combination, with a reciprocating slide, and a rotary grinding wheel carried by the said slide;

of a crank-disk and a connecting-rod for reciprocating the slide, a toothedwheel secured to the crank-disk, a pivoted lever, and a toothed drivin pinion carried by the lever and journaled eccentric of its pivot and normally engaging with the said wheel, said lever and crank-disk being provided with interlocking portions which are moved into engagement to stop the slide when the pinion is *moved out of engagement with the wheel.

2. In a grinding machine, the combination, with a reciprocating slide, of a head carried by the slide and provided with a bearing, a carrier adjustable longitudinally inthe bearing, means for clamping the carrier in the bearing, antifriction shaft bearings arranged in the said carrier, a shaft journaled in the antifriction bearings and provided with means for revolving it, and a grinding wheel secured on the said shaft.

3. In a grinding machine, the combination, with a reciprocating slide, and a rotary grinding wheel carried by the said slide; of a spindle for supporting the article to be ground, and intermediate driving mechanism operatively connecting the said slide and spindle so that the'spindle is revolved termediate driving mechanism 0 eratively connecting the said slide and spin le so that the spindle is revolved first in one direction and then in the other to correspond with the reciprocating movements of the slide and the grinding wheel.

5. In a grinding machine, the combination, with a rotary grinding wheel, and driving devices for reciprocating it; of a supporting frame, a rotary spindle, for carryin the article to be ground, mounted in the frame, a spiral gear wheel operatively connected with the said spindle, a shaft journaled in the frame and provided with driving mechanism for revolving it, a sleeve mounted on the said shaft, a spiral gear wheel secured to the said sleeve and engaging with the aforesaid spiral gear wheel, a spacing disk secured to the sald shaft, and a casing connected with the said sleeve and provided with a disengageable locking device for engaging with the spacing disk, so that the casing and sleeve can be revolved by hand to adjust the position of the rotary spindle and the article when the casing is unlocked from the spacing'disk.

6. A machine for grinding hobs, or millingand like cutters in which an abrasive wheel is carried by a vertically reciprocating slide having a slow cutting stroke and a quick return stroke, the said slide carrying a rack which operates means for rotating the hob or cutter, whereby the hob or cutter is rotated first in one directioncand then in the other at a speed varying with that of the vertical movements of the abrasive wheel, substantially as herein shown and set forth.

7. A machine for grinding hobs or milling and like cutters comprising a standard,

a slide movable vertically thereon, means'to operate said slide to give a slow cutting movement anda quick return movement, a cross slide carrying a universal head sup porting an abrasive wheel, means to drive said abrasive Wheel, a hob supporting spindle, and means includin indexing mechanism to cause the hob to ie rotated forward and backward at the required speed relatively to the rate of upward and downward movement of the abrasive wheel, substantially as herein shown and set forth.

8. Ina machine for grinding hobs or milling and like cutters the combination with a vertically movable slide carryin an abrasive wheel head, of a link pivotal y connected to the slide and to a rotatable disk, whose center is offset from the line of movement of the slide, a gear rotatable with the disk, a pinion carried by a pivoted lever, means to drive the pinion, a spring acting on the lever to normally hold the pinion in mesh with the gear on the disk, and a block carried by the lever and adapted, on the lever being rocked to withdraw the pinion from mesh with the gear, to enter a recess in the periphery of the disk and cause the slide carrying the abrasive wheel to come to rest in a definite position, substantially as herein shown and described.

9. In a machine for grinding hobs or milling and like cutters thecombination, with a vertically reciprocating slide and a cross slide mounted thereon, of a dished casting mounted to swivel on the end ofvsaid cross slide, a carrier slidably supported in an openm in a boss on the casting, ball and thrust bearings within said carrier supporting a spindle on which the abrasive wheel is secured, a pulley fast on said spindle and guide pulleys carried by an arm attached to or integral with the carrier, all substantially as herein shown and set forth.

In testimony whereof we aifix our signatures in the presence of two witnesses.

Witnesses:

T. E. WHITELEY, C. E. HINCHLIFF.