US2553699A

US2553699A - Tool feeding device

Info

Publication number: US2553699A
Application number: US595312A
Authority: US
Inventors: Eric C Brodin
Original assignee: SKF Industries Inc
Current assignee: SKF Industries Inc
Priority date: 1945-05-23
Filing date: 1945-05-23
Publication date: 1951-05-22
Anticipated expiration: 1968-05-22

Description

May 22, 1951 E. (3. BROWN TOOL FEEDING DEVICE Filed May 23, 1945 jlwenioz-ex 5y csfirneas Patented May 22, 1951 TOOL FEEDING DEVICE Eric C. Brodin, .lenkintown, Pa., assignor to SK F Industries, Inc, Philadelphia, Pa-., a corporation of Delaware Application May 23, 1945, Serial No. 595,312

' 7 Claims.

This invention relates to means for relatively feeding the cutting or grinding elements of machine tools and the work, and one object of the invention is to provide a feed device affording a higher degree of precision than can be obtained by the prior conventional feed devices.

It is customary to mount cutting and grinding tools on posts or heads which are movable on suitable guide means to and from the work. This method of feeding the tool to the work, while in general satisfactory, tends to fail when small tolerances are involved, andparticularly when it is necessary to reproduce on a quantity basis pieces having highly precise dimensions. The aforedescribed conventional feed devices are frequently incapable of relocating the tool with suf ficient accuracy in a given operating position as required when passing rapidly from one piece to another. This is due apparently to variation in friction between the traversible tool support and its guide.

It is a primary object of this invention to provide a feed device which will eliminate these variables and which will thereby afford a feed of relatively high precision.

More specifically, an object of the invention is to provide a feed device wherein the advance of the tool. to the work may be effected without movement of the tool support as a whole and in a manner to substantially eliminate variations arising from frictional eiiects.

The invention will be more readily understood by reference to the attached drawings wherein:

Fig. 1 is a side view of a holder for-a grinding wheel wherein provision is made for feeding the wheel to the work in accordance with the principle of the invention;

Fig. 2 is a somewhat enlarged fragmentary side and partial sectional view of a holder illustrating a modification within the scope-of the invention;

Figs. 3, 4, and 5 are sectional views of tool holders illustrating still further applications of the inventive principle, and

6 is a side elevational view illustrating another embodiment within the scope of the invention.

The embodiment of the invention illustrated in Fig. 1 of the drawings comp-rises a holder l wherein is iournaled a grinding wheel -2. This wheel may be rotated in the holder by any conventional means, and since the wheel rotating devices form no immediate part of the invention, the elements thereof have not'been included in the drawings. The holder l departs from the conventional in having therein .a .deep slot 3 which forms .a relatively narrow. neck portion 4 between the front terminal end '5 of the holder, wherein the wheel 2 is journaled,..and'.the body 6 of the holder. Threaded into an upstanding portion l' of the body 6 is a feed screw 8, the inner end of which traverses the outer end of the slot 3 and engages the side of the end .portion 5; The other end of thescrew is prov-idedlin the present instance, with a suitable handle 9 by means of which th screw may be turnedso as to exert pressure upon the end portion 5 of the holder, to thereby spring the relatively narrow neck portion 4, and to displace the grinding wheel 2 with respect to the body of the holder.

Assuming now that the holder I is rigidly supported in the machine tool in a position wherein the grinding wheel 2 may contact the work, or

lie in close proximity thereto, it is apparent that by turning the screw 8, the wheel 2 maybe advanced or fed into or against the work. The feeding movement of the wheel 2 is effected entirely by fiexure of the material of the holder i in the neck 4. Since the elasticity of steel or other metal from which theholder 1 maybe formed is a constant, a given fiexure of the holder will advance the tool always to the same extent. It, therefore, means be provided, such, for example, as a dial in association with the screw for indicating the positions of the latter in the holder, assurance is aiiorded that in any fixed position of the holder 1, a given position of the screw will always correspond to a given position of the grinding wheel 2 with respect to the work. The device, therefore, affords a means for moving the wheel 2 exactly to the same working position with respect to any number of like work pieces passed successively through the machine. 7

In Fig. 2 the construction of the holder, designated in this instance by the reference numeral it, is similar to that described above and illustrated in Fig. l, with the exception that in this instance the feeding of the grinding wheel 2! is eiiected through the medium of an hydraulic means instead of by the mechanical device of the previously described embodiment. In this instance, an expansible diaphragm member 28 is mounted in the outer end of the slot 23 in a manner such that when hydraulic pressure is applied thereto, -as by way of a duct 29, the resulting expansive pressure of the member between the sides of the slot 23 will cause a flexure of the holder le'inthe neck portion 24 thereof in the manner described above.

In Fig. 3 the holder 39 is formed, in efifect, with a plurality of slots 33 arranged serially, and each of the slots is provided at its outer end with an expansible diaphragm device 38 connected to a common hydraulic system which may be designated generally by the reference numeral 39. Application of hydraulic pressure to the elements 38 results in a flexing of the metal of the holder in the several neck portions 34 with the result that the grinding wheel 32 is displaced in obvious manner. This embodiment of the invention difiers from those illustrated in Figs. 1 and 2 in that it affords a substantially straight line feeding movement of the grinding wheel 32 as indicated by the arrow A as distinct from the arcuate movements of the grinding wheels 2 and [2 in the embodiments of Figs. 1 and 2 respec tively as indicated by the curved arrows A and A of those figures. In this case also, it is apparent that a relatively small expansion of the elements 38 will efiect a relatively great movement of the grinding wheel 32, the movement of the wheel corresponding to the sum of the expansion movements of the individual elements 38.

The holder shown in Fig. 4; is essentially the same as the holder 30 illustrated in Fig. 3 with the exception that in this instance, a single hydraulic element 48 is employed in lieu of the several such elements 38 of the previously described embodiment. The element 438 is located to the rear of the serpentine formation which produces the

slots

43, 43, and the flexible neck portions 44; and a rod 49 extends through apertures in the walls of the nearer slots 43 and is secured in the end portion of the holder which journals the grinding wheel 42. It is apparent that in this case expansion of the element =38 will advance the wheel 42 by flexure of both of the neck portions 44. In this case also the movement of the grinding wheel is a linear one, as indicated by the arrow A In the embodiment of the invention illustrated in Fig. 5, the grinding wheel 52 is journaled in a block 53, which block is supported on upright parallel

flexible arms

54, 54. These arms are secured at the bottom to the body 55 of the tool holder. The holder also comprises an upwardly extending portion 56 in which is threaded a feed screw 51, the inner end of which bears against the side of one of the flexible members 54 at one side of the block 53. Advancement of the screw 51 will efiect a flexure of the arms 5 and a feeding movement of the Wheel 5'! in the direction of the arrow A The arms 5 being resilient will return to their original positions when the screw 5'! is backed away in the upright 55.

It will be understood that the aforedescribed devices may be used to feed the work relative to the tool, instead of the tool into the work, and

that such reversal is contemplated as falling within the scope of the invention. In Fig. 6, for example, the work 58 is shown as supported in a holder 59 comprising a typical flexible portion Gil, said portion connecting the two parts 6i and 62 of the holder and providing for relative displacement of these parts in the manner previously described. The work 58 is held in the part 6!, and a screw 63 threaded in the relatively fixed part 62 provides for displacement of the part Si and of the work piece in a manner to feed the work against a grinding wheel 64, the latter being mounted in a structure 55. Obviously, hydraulic or other suitable means may be used in lieu of the screw 63 to eifect the feeding of the work piece.

I claim:

1. In a tool feeding device, a holder having a recess terminating at the bottom in a resilient portion of the holder, means for mounting a tool on the holder at one side of said recess, and a fluid pressure system including a fluid-actuated expandable element confined in and between the sides of said recess and through which accurate- 1y regulated pressure may be applied to said sides to flex said resilient portion and to efiect a displacement of the tool with respect to that part of the holder on the other side of the recess.

2. In a tool feeding device, a holder having a series of more or less parallel recesses extending inwardly from opposite sides of the holder and each terminating at the bottom in a resilient portion of the holder, means at one end of said series for mounting a tool on the holder, and means operatively associated with the holder at the other end of said series for exerting pressure tending to flex the said resilient portions all in the same direction to thereby displace the tool mounting with respect to that part of the holder at the said opposite end of the series.

3. In a tool feeding device, a holder having a series of more or less parallel recesses extending inwardly from opposite sides of the holder and each terminating at the bottom in a resilient portion of the holder, means at one end of said series for mounting the tool on the holder, and means for exerting pressure to simultaneously flex the resilient portions unidirectionally to displace the tool mounting with respect to that part of the holder at the other end of said series.

4. In a tool feeding device, a holder having a series of more or less parallel recesses extending inwardly from opposite sides of the holder and each terminating at the bottom in a resilient portion of the holder, means for exerting pressure to vary the distance between the portions of the holder on opposite sides of said series of recesses by fiexure of said resilient portions, and means on one of said side portions for mounting a tool on said holder.

5. A tool feeding device according to claim 3 wherein the said pressure-exerting means is fluid-actuated.

6. A tool feeding device according to claim 3 wherein the said pressure-exerting means includes at least one fluid-actuated expandable element.

'7. In a device for efiecting relativ feeding movements between tool and work elements, a holder having a free end portion formed by a recess terminating at the bottom in a resilient portion of the holder, means for mounting one of said elements on the free end portion of the holder at one side of said recess, and means for exerting pressure on the holder at points on opposite sides of said recess so as to flex said resilient portion and to efiect a displacement of said free end portion and the mounted element with respect to that part of the holder on the other side of the recess, said pressure means operating continuously to control fiexure of the said resilient portion, and said free end portion being otherwise unsupported against the thrusts resulting from reaction of the said tool and Work elements and being free for displacement by action either of said pressure means or of the said resilient portion of the holder.

ERIC C. BRODIN.

(References on following page) 5 REFERENCES CITED Number The following references are of record in the 11234369 file of this patent: UNITED STATES PATENTS 5 213721324 Number Name Date 483,749 Rogers Oct. 4, 1892 522,361 Worden July 3, 1894 Number 741,449 Brandstetter Oct. 13, 1903 ,0 883,650 Landis Mar. 31, 1908 16 133,865

Name Date Kelly July 31, 1917 Gould Feb. 25, 1936 Hawes Nov. 24, 1936 Gould Apr. 3, 1945 FOREIGN PATENTS Country Date Great Britain Feb. 27, 1905 Switzerland Sept. 13, 1927