US1709617A - Grinding machine - Google Patents

Description

Ap 16, 1929. B. M. w. HANSON GRINDING MACHINE Original Filed Dec. 18, 1926 4 Sheets-Sheet gwumtor I i w (5M0 1.5mm

I 6mm April 16, 1929.

B. M. W. HANSON GRINDING MACHINE Original Filed Dec. 18, 1926 4 Sheets-Sheet 2 we 5 1 f .M w v w v y April'l6, 1929. a. M. w. HANSON GRINDING MACHINE Original Filed Dec. 18, 1926 4 Sheets-Sheet 5 Patented A r. 16, 1929.

UNITED STATES PATENTTOFFICE.

BENGT M. W. HANSON, DECEASED, LATE OF HARTFORD, CONNECTICUT, BY EINAR A. I HANSON, OF WEST HARTFORD, CONNECTICUT, AND CLARENCE E. WHITNEY, OF HARTFORD, CONNECTICUT, EXECUTORS; NOW BY RESIGNATION A. HANSON,

SOLE EXECUTOR.

GRINDING MACHINE.

Original application filed December 18, 1925, Serial No. 76,301. Divided and this application filed August 4, 1927. Serial No. 210,688. g

This is a division of the Bengt M. W. Hanson, deceased, application Serial No. 76,301, filed December 18, 1925.

The present invention relates to grinding machines, and particularly to a machine for grinding fluted tools, such as taps.

An object of the invention is to provide a simple and compact machine by means, of-

which pieces of work may be very conveniently, accurately and rapidly ground. More especially, my machine is adapted for chamfering taps and the like so as to give the same the desired taper and relief.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will 2 be exemplified in the construction hereinafter set forth and the scope of the application ofwhich will be indicated in, the ap pended claims.

In the accompanying drawings, wherein is shown for illustrative purposes one of the many embodiments which the present inven tion may take:

Figure 1 is a front view of the, machine; Fig. 2 is an end view thereof; Fig. 3 is a left hand end view (referring to Fig. 1) of the work support and holder,

parts being broken away for the purpose of illustration Fig. 4 is a horizontal sectional view taken substantially on line 44 of Fig. 3;

Fig. 5 is a detail view of the means for clamping the head stock in place;

Fig.6 is a vertical sectional view through the work support, the bearing for this sup- 11 on which a grinding wheel slide 12 is port, and the gearing .associated therewithp I-Fl at right angles to the grinding wheel spindle. For the urpose of so adjusting this slide, there" is ournalled against longitudinal movement relative thereto a screw 17 having threaded engagement with a nut 18 carried by a bracket 19 fixed to the side of the standard 10 and overhanging the slide. Any suitable means may be associated with the grinding wheel for truing the same. In the present illustrative disclosure, this truing means includes a diamond point 25 supported in a horizontal swinging arm 26 pivoted to the grinding wheel slide as at 27. The swinging arm mayhave a handle 28 for moving the diamond point back and forth across the peripheral faceof the grinding wheel in order to true the latter.

J ournalled in suitable bearing brackets 35 and extending from the rear of the standard 10 is a main or drive shaft 36 having the usual fixed and loose pulleys 37 which may be drivenby a belt 38. The grinding Wheel spindle 14 is driven from the main shaft 36 in the following manner: Located in front and at the base of the standard 10 is an intermediate shaft 40 driven by a belt 41 passing about pulleys 42 and 43, respectively, fixed to the drive shaft 36 and the intermediate shaft 40. Also fixed to the intermediate shaft 40 is a stepped pulley 44 about which passes a belt 45 which runs over a stepped pulley 46 fixed to the grinding wheel spindle 14 between the bearings 13. It will be noted, particularly from Figs. 1 and 2, that the belt 41 passes through-the standard 10, the standard having suitable openings to this end. The belt 38 may be shifted to throw the power on and off of the machine by means of a rod 47 connected by a lever 48 to the usual fork 49.

The machine has a support adapted for ancylindrical post 51 journalled in the bearing 52 of a bracket 53 secured to, and extending laterally from, the standard 10. Mounted on the arm 50, for rocking movement, is a work holder which includes a rocking bed 55. By preference, in order to eliminate friction and wear and to provide for a smooth rocking movement of the bed 55, the latter is fulcrumed on knife edges 56. On the outer end of the rocking bed is a bearing box in which is journaled a sleeve 61 supporting 'a work spindle 62 having on its forward end means for engaging the tap or other piece of work to be sharpened. In the present instance, the spindle is shown as having a work center 63 and a dog 64. The spindle is keyed to the sleeve as shown. The Work spindle 62 is journalled in, but held against longitudinal movement relative to, a head stock 65 adj ustably securedto the forward face ofthe rocking bed 55. In the present instance, the head stock, shown most clearly in Fig. 5, is slidably mounted in a guideway 66. on therocking bed and is secured in place by a clamping bolt 67 coo crating at its inner end with a nut 68 slidab y mounted in a T-groove- 69. 70 designates a tail stock having a work center 71 aligned with, and opposed to, the center 63. The tail stock is arran ed to be adjusted and clamped in adjustab e position on the rocking bed in the same manner as the head stock. It will be noted, particularly from Figs. 3 and 7, that the head and tail centers are disposed (in any angular position of the support 50) in a line which is substan tially normal to the axis 112 a: about which the support is adjustable. It may also be noted that the line on which the rocking bed is fulcrumed is substantially normal to the axis w-w. This means that the work centers and the knife edges are located in'a vertical place which includes'the axis ww of the support.

The means for imparting a rocking movement to the rocking bed in accordance with the desired relief on the work will now'be described withparticular reference to Figs. 1, 3 and 4. Journalled in the bearing box 60 in parallelism with the work spindle 62 is a shaft 75 provided with a'plurahty of pattern cams 7 6*, 76", 76 and 7 6 the peripheral C011. tours of which differ from one another. For

instance, the first pattern cam 7 6 may have two lobes; the next one, 7 6", three lobes; the next one four lobes, and the last one five lobes so that the cams respectively correspond to two, three, four and five fluted tools. The shaft 75 is driven in timed relation with the speed gearing which may consist of a pair of gears 77 and 78 fixed to the work spindle sleeve 61 and gears 79 and 80 keyed to, and shiftable on, the shaft 75 and adapted to respectively mesh with the gears 77 and 78. The gears 7 8 and 80 may have a ratio of one to two, and the gears 77 and 79, a ratio of one to one. For the purpose of shifting the gears 79 and 80, there is provided a. yoke or fork 81 fixed to a slidable rod 82 having a knob or handle 83. Adapted to be selectively en gaged with the pattern cams is an abutting or rest member which is here shown as having the form of a roller 85 journalled in a slide 86 mounted on a link or lever 87. The slide 86, which is mounted in a groove 88 in the upper face of the link 87, may be moved longitudinally of the shaft 75 by means of a handle 89. In order to prevent accidental displacement of the slide, there is a spring pressed plunger 90 adapted to selectively en-g gage recesses 91 provided in the slide.

The linkor lever 87 is pivoted at its rear end on a pin or stud 94 on the rocking bed and supported at its forward end on a fulcrum 95 which is adjustable laterally of the axis about which the rocking bed is adapted to be rocked. In the present instance, the fulcrum member is in the form of a pin carried by a block 96 which is adapted to be clampedby a bolt 97 in any desired position of adjustment on an extension 98 extending forwardly from the free or left hand end of the support-50. The clamping bolt 97 has, on its outer end, a handle 99 and, on its inner end, a nut 100 located in a T-groove 101 in the side face of the extension 98.

It will be noted that, with the arrangement described, a very flexible selectivity over aconsiderable range may be had so that any tap having a practical number of flutes may be operated upon; also, any desired extent of relief on the lands or teeth of the work may be had. In thetease of a two fluted tap, the gears 77 and 7 9 will be engaged and the roller 85 will be engaged with the cam 76 having two lobes. Similarly, in cases where three, four or five fluted tools are to be operated upon, the gears 77 and 79 will be engaged and the roller 85 will be respectively engaged with the earns 76", 76 and 76 In the event that a six fluted tap is to be ground, the gears 78 and 80 are engaged and the roller 85 is engaged with the three lobe cam 76, as shown in Fig. 4. The roller will be engaged with the cam 76, and this cam will be driven through the gears 78 and 80, where an eight fluted tap'is to be ground. In the event of a greater amount of relief desired, the farther 1 will the abutment or fulcrum 95 be adjusted spindle 62, as, for instance, through change away from the line of the knife edges 56. A

lesser extent of relief may be had by adjusting the abutment 95 towards the knife edges 56.

The lands of the tap operated upon must, of course, bear the proper relation to the lobes of the pattern cam which is employed for rocking the work holder. To facilitate bringing about this relation, an indicator is provided for denoting the position of the rocking bed with respect to the grinding wheel. This indicator includes a pointer or lever 102 pivoted either on the rocking bed 55 or the support 50 and adapted to engage the other of these elements. In the present instance, the pointer is pivoted on the rocking bed and has one end engaging or resting upon the extension or arm 98 of the support. The other end of the pointer moves with respect to the scale 103 which may be provided on a casing 10a within which the pointer is housed.

In accordance with the present invention, a novel drive is provided for the work spindle 62, this drive being such as to permit of adjustment of the work support and to reduce to a minimum the number of parts required. This drive, in the present instance, includes a stepped pulley 105 on the main drive shaft 36; a stepped pulley 106 on a shaft 107; and a belt 108 passing about these pulleys. The shaft 107 is journalled in a bearing bracket 109 secured to, and extending laterally from, the standard 10. The axis of the shaft 107 is normal to theaxis wzv about which the support 50 is adjustable. Secured tothe lower end of the post 51, as by means of pins 112, is a gear box 113 whichis adapted to be turned with the arm 50, this box having a horizontally extending slot 114 to accommo date the shaft 107. The shaft 107 carries a bevel pinion 115 which meshes with a bevel gear 116 housed within the casing 113 and fixed to the hub of a gear 117 journalled on a pin 118 located axially in the lower end of the post 51 and secured thereto by a set screw 119. The gear 117 meshes with a gear 122 loose on a shaft 123 one end of which is journalled in a bearing 124; provided on the gear box 113. The other end of the shaft is journalled in the lower end of a bracket 125 depending from the free end of the support or arm 50.. The gear 122 is adapted to be fixed, at will, to the shaft 123 by a clutch sleeve 126 keyed tov the shaft 123 for sliding movement. This sleeve may be engaged and disengaged with the gear 122 by moving in. the proper direction a handle 127 fixed to a shaft 128' 131 passing about pulleys 132 and 133, re

spectively fixed to the outer ends of the sleeve 61 and the shaft 123. It will be noted that this driving mechanism is very simple and economic in construction and arrangement and yet it is very effective in operation. The support 50, together with the parts thereon, may be angularly adjusted in order to bring the work into proper angular relation to the grinding wheel 15 without disturbing,.in any way, the driving connections or other parts of the machinel The operation of the machine will now be briefly explained. The tap to be ground is positioned between the centers63 and 71, as shown most clearly in Fig. 7, the head and tail stocks first having been properly adj usted longitudinally of the rocking bed in order that the grinding wheel may properly en "gage the forward end of the tap which is to rocking bed will be in its foremost lowest position and which position will be indicated by the pointer 102; that is to say, the low point of one of the lobes of the pattern cam to be em ployed, and which low point corresponds to the high point of a land of the tap, will be resting on the roller 85. The tap, with the parts in this position, will be angularly adjusted upon the centers so that the high point of a land of the tap will be directly opposed to the grinding wheel, as shown in Fig. 8. The support 50 is angularly adjusted so that the axis of the tap is brought to an angle relative to the axis of the grinding wheel in accordance with the taper to be given: to the tap and, to facilitate this adjustment, there may be provided a scale 135 on the upper end of the gear box 113 and a cooperating scale mark 136 on the bearing 52. The mechanism having been properly set up, power is now thrown onto the work spindle, and the grinding wheel is advanced into engagement with the work by moving the slide 12 through the screw 17. During the grinding operation,

the patterncam, which rests upon the roller 85, will impart a rocking movement to the tap corresponding to the circumferential contour to be given thereto. It is important to note that the grinding wheel 15 is adjustablein a. plane passing centrally through the grinding wheel and including the axis about which the support 50 isadjustable. The tail stock extends laterally very slightly beyond the axis of the tap. With this arrangement, the tap may be quickly and accurately adjusted with respect to the grinding wheel; the grindin'g wheel may be properly adjusted and fed with respect to the tap; and, as will be seen, particularly from Fig. 7, in no position of adjustment of the support will the head or tail stocks interfere with the grinding wheel. The grinding wheel may extend beyond the forward or smaller end of the tap, as shown in this figure.

As many changes could bemade in the above construction and many apparently widely different embodiments of this invention could be made without departing from a matter of language, might be said to fall therebetween.

What is claimed is:

1. In a machine of the character described, a support mounted for angular adjustment about a vertical axis, a rocking bed mounted on said support for rocking movement about an axis substantially normal to the first mentioned axis, means on said rocking bed for rotatably supporting a piece of Work with its axis substantially parallel to the second mentioned axis, a grinding wheel mounted for adjustment in a plane passing centrally through the cutting edge of the wheel and including the first mentioned axis, and means for rocking said bed.

2. In a machine of the character described, a standard, a bearing thereon, a laterally extending arm journalled in said bearing, a rocking bed fulcrumed on said arm, head and tail stocks on said rocking bed for rotatably supporting a pieceof work, a grinding wheel slide adiustably mounted on the top of said standard, a cylindrical grinding wheel car- {Jied by said slide, and means for rocking said 8. In a machine of the character described, a tool, a work spindle, and means for rela tively moving the same towards and away from each other in accordance with the circumferential contour to be given to the work, said means comprising a plurality of cams, each having lobes differing in number to those on the others, means for driving said cams in timed relation to said work spindle and including speed change mechanism, and an abutment adapted to be selectively engaged with said cams, a,

d. In a machine of the character described, a tool, a rocking bed movable relative thereto and having a spindle for rotatably support-- ing a piece of work, a shaft journalled in said bed, a plurality of cams fixed on said and each having lobes differing in number to those on the others, change speed gearing be tween said spindle and shaft, and an adjust able roller adapted to be selectively engaged with said cams.

5. In a machine of the character described, a support, a fulcrum thereon, a rocking bed on said fulcrum, a link, a fulcrum for link and mounted on said support for movement towards and away from said first tioned fulcrum, means for pivotally connecting said link to said bed between said fulcrums, a pattern cam journalled in said rocking bed, and an abutment on said link and engaging said cam.

6. In a machine of the character described, a support, a rocking bed fulcrumed thereon, a link, a fulcrum for said link mounted on said support for ad'ustment to and from the fulcrum of said rocking bed,-means pivotally connecting said link to said rocking bed, a plurality of cams on said rocking bed, a slide on said link adapted to be adjusted longitudinally of the axes of said cams, and a roller on said slide adapted to be selectively engaged with said cams.

7. In a machine of the character described, a frame having a bearing, a support having a post turnable in said bearing, a work holder on said support having a work spindle, a member on the lower end of, and movable with, said post, a bracket armdepending from said support, a shaft journalled in said arm and member and normal to the axis of said support, a connection between the outer ends of said shaft and said spindle, a gear on said shaft, a shaft journalled in said frame and having a gear, and gears between said men tioned gears and journalled on. the lower end of, and co-arially with, said post.

8. In a machine of the character described, a frame having a bearing, an angularly adjustable support having a post in said bearing, a work holder on said support having a work spindle, a gear box secured to the lower end of, and turnable with, said post, a bracket arm depending from said support, a shaft journalled in said bracket arm and gear box, a connection between said shaft and spindle, a gear within said gear box and on said shaft, a shaft journalled in said frame and having a gear within said box, a bearing member on the lower end of, and co-arial with, said post, and a pair of gears journalled on said bearing member and respectively engaging said mentioned gears, said gear box having a slot for accommodating said second mentioned shaft 9. In a machine of the character described, a frame or standard, a grinding wheel spindie mounted thereon, a bearing on said frame, a laterally extending support having a post turnable in said bearing, a work holder on said support having a work spindle, a gear box fixed to the lower end of, and turnable with, said post and support, a bracket arm depending from the free end of said support, a shaft journalled in said member and arm, a connection between said shaft and spindle, a drive journalled on said frame behind the same, an intermediateshaft front of said frame, belt between said drive shaft and intermediate shaft passing t ugh said frame, belt between said whe spindle intermediate shaft, a d1,

journalled in said frame, gearing within said box and between said driven shaft and first mentioned shaft, and a belt between said driving shaft and driven shaft.-

' 10. In a machine of the character described, a support element, a rocking bed element fulcrumed thereon, means for rocking said bed about its fulcrums and including a rotatable pattern cam, and means for indicating the angular position of said cam and including a pointer'pivoted on one of said elements and engaging the other one.

11. In amachine of the character described, a support element, a rocking bed element fulcrumed thereon, a spindle for rotatably holding a piece of work on said rocking bed, means for rocking said bed and including a circumferentially contoured cam driven in timed relation to said spindle, and means for indicating the angular position of said cam and thereby the relation of the Work relative to the operating tool and including a lever pivoted on one of saidelements and engaging the other one, and a scale with avhich said lever cooperates;

EINAR A. HANSON, CLARENCE a. WHITNEY,

Emeoutors of Bengt M, W, Hanson, De

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