US2870658A

US2870658A - Machine tool for boring intersecting bores

Info

Publication number: US2870658A
Application number: US508883A
Authority: US
Inventors: Sr George Melling
Original assignee: Melling Tool Co
Current assignee: Melling Tool Co
Priority date: 1955-05-17
Filing date: 1955-05-17
Publication date: 1959-01-27
Anticipated expiration: 1976-01-27

Description

Jan. 27, 1959 G. MELLING, SR

MACHINE TOOL FOR BORING INTERSECTING BORES 2 Sheets-Sheet 1 Filed May 17, 1955 INVENTOR. 620/" a /7a/// /7;JZ

BY @552 Q 844/ iz/anazz G. MELLING, SR

2 Sheets-Sheet 2 INVENTQR.

f/Zd/Vk Jan. 27, 1959 MACHINE TOOL FOR BORING INTERSECTING BORES Filed May 17, 1955 & 7w I NW M m u l v ww M&\ aw J \Qw RN N W Qnfi \w WH- Ill H I I v I III QM W I \r w I @w w hwl mm NW ll |||I United States Patent MACHINE TOOL FOR BORING INTERSECTING BORES George Melling, Sr., Jackson, Mich., assignor to Melling Tool Company, Jackson,' Mich.

Application May 17, 1955, Serial No. 508,883

14 Claims. ('Cl. 773) This invention relates to improvements in machine tool for boring intersecting bores. The principal objects of this invention are:

First, to provide a machine for concurrently forming intersecting bores in a work piece with the centers of the bores accurately controlled.

Second, to provide a machine that neutralizes the side thrust on a boring too-l where one side of the tool is exposed and inoperative.

Third, to provide novel means for supporting and locating the spindle of a boring tool so that the spindle bearings are not subjected to excessive side thrust thus lengthening the lifeof the machine and bearings.

Fourth, to provide a machine particularly adapted for boring the chamber of a .gear pump to simultaneously and accurately cut the chambers for the meshing gears of the pump.

Other objects and advantages of the invention will be apparent from a consideration of the following description and claims. The drawings, of which there are two sheets, illustrate a highly practical form ofthe invention' Fig. l is a fragmentary plan view of the boring machine set up and arranged to commence the boring operation on a gear type pump.

Fig. 2 is a fragmentary longitudinal cross sectional view through the machine taken along the plane of the line 22 in Figs. 3 and 4.

Fig. 3 is a vertical transverse cross sectional view taken along the plane of the line 33 in Figs. 1 and 2.

Fig. 4 is a fragmentary vertical cross sectional view taken along the plane of the line 4 in Figs. 1 and 2.

Fig. 5 is a fragmentary enlarged view similar to Fig. 3 illustrating in greater detail the mounting of part of the backing rolls relative to the spindles of the machine.

Fig. 6 is a fragmentary transverse cross sectional view through the cutting tools taken along the plane'of the line 6-6 in Fig. 2.

Fig. 7 is a plan view of a gear pump housing with the gears assembled therein to illustrate the chambers cut by the tool of this invention.

As is well known many liquid pumps of the gear type are employed particularly for pumping lubricating oil in automobiles. These pumps include a body or casting in which two intersecting cylindrical chambers are formed for the reception of the meshing gears of the oil pump. Shaft journals are formed in the body concentric with the gear chambers to receive the shafts of the two gears; One of these shafts commonly extends from the gear body as a drive shaft and the body is commonly provided with a cylindrical neck around the drive shaft by means of which neck the pump body is mounted on its supporting structure such as the cylinder block of an internal combustion engine.

It is well known that the dimensions and relative locations of the gear shaft journals and pump chambers must be accurately controlled to provide an efficient pump. Specifically the shaft journals must 'be accurately spaced 7 and the journals and pump chambers'inusfbe concentric 870,658 Patented Jan. 27, 1959 where it rotates through the intersecting portion of the gear chambers thus creating a high side thrust on the boring tool that either moves the boring tool off center of the gear journal or applies excessive loading to the bearings which rotatably-support the boring tool.

The drawings illustrate a base 1 having work holding chuck 2 and clamp 3 on one end and parallel rods 4 forming a slideway on the other end. The work holding clamp 3 is pivotally supported by the bearing bracket 5 and actuated by a fluid cylinder 6 to clamp the work or pump body 7 opposite the outer ends of the slide rods 4. Slidably supported on the rods 4 is a head generally indicated at 8 and carrying tool drills 9 and 9A for forming the shaft bearings in the work and boring tool cutters 10 and 10A for forming the work chambers in the work. The details of the work holding chuck and clamp form no part of the present invention and so are not described in greater detail.

The head 8 consists of a base plate 11 having an outer journal block 12 and inner journal block 13 formed on the upper side thereof. An intermediate journal block 14 is positioned on the plate intermediate of the

blocks

12 and 13. An air cylinder 15 is mounted on top of the head 8 and has its piston rod'lfi fixedly connected to an anchor 17 on the inner end of the base 1. The outer bearing block 12 defines closely spaced intersecting bores 18 and 13A in which are mounted bearings 19 for rotatably receiving a drive spindle 20 and a counter spindle 21. The intermediate bearing block 14 defines bores 22 and 22A which also rotatably receive the drive spindle and counter spindle. Needle bearings 23 are mounted in the bores 22 and 22A. The inner bearing block 13 defines a single bore 24 through which the drive spindle projects. The spindle 20 also projects through the anchor 17 and is splined as at 25 forming a slidable driving connection to the drive pulley 26. The drive pulley 26 is arranged to be driven by suitable means such as the belt 27 and motor 28.

The inner bearing block 13 carries a thrust bearing 29 engageable with the inner end of the counter spindle 21 and adjustable axially of the spindle by means of the adjusting screw 30-. Athrust bearing 31 for the drive spindle is positioned against the intermediate bearing block 14 where it is acted upon by the end of a small pinion gear 32 on the drive spindle. The gear 32 is con stantly in driving engagement with an equal pinion gear 33 on the counter spindle.

The outer ends of the

spindles

20 and 21 are provided with'enlarged collars 34 that are incontacting rolling engagement at the outer face of the outer bearing block 12. A cover 35 encloses the collars 34- and carriesdust seal 36 coacting with the outer ends of the spindles. The outer ends of the spindles are provided with tapered bores 37 for removably receiving the tapered shanks 38 of cutting tools 10 and'10A; Theouter ends of the cutting tools are in turn axially boredand tapered as at 39 to receive the shanks of the drills or boring bits 9 and 9A.

As is best illustrated in' Figs. 2 and 4 the outer face of the bearing block '12 carries backing rolls 40 that engage the outer sides of the collars 34 and backing rolls 41 that engage the under or diverging-sides of the collars 34. The inner side of the bearing block 12 carries backing rolls 42 that engage the outer sides of the

spindles

20 and 21 and a backing roll 43 that engages the under or diverging side of the counter spindle 21. A back roll 4d engages the top or converging side of the'drive spindle adjusted to bring the backing rolls into proper supporting engagement with their associated spindles. Clamping screws 48 clamp the pins 46 in their adjusted positions;

The top of the outer bearing block 12 is provided with holes 49 (see Fig. l) opening to the spindles 2t} and 21 between the bearings to permit a wedge to be driven into slots 50 in the spindles for driving out the tapered tool shanks 38.

The outer ends of the tools and 10A are best illustrated in Fig. 6 and include radially extending arms 51 having hardened cutter blocks 52 on their leading edges. The tools are mounted on the spindles so that the arms 51 alternate or mesh as the tools and spindles are rotated in the directions indicated by the arrows. It will be notedthat the cutting force of one cutter is counter balanced by thecutting force of the other cutter as the cutters form the two intersecting gear chambers 53 in the pump body 7. There is, therefore, little side thrust on the tools or spindles tending to mislocate the tools or to move the head 8 bodily out of its proper alignment with the chuck 2. Such individual side thrust asmay be created in each chuck is effectively controlled by the

backing rolls

40, 41; 42 and 43. The backing rolls and the rolling engagement between the collars 34 relieve the spindle bearingsof excessive side loads so the machine has a relatively long operating life without any loss of accuracy in the work produced.

More particularly, the backing rolls 41 on the underside of the spindles support the reaction forces created by the upward. cutting action of the cutters 52. At the inner side of the bearing block 12 the

small diameter pinions

32 and 33 create forces tending to separate the two spindles. The backing rolls 42 sustain and resist the laterally directed forces While the driving force on pinion 33 tending to force the counter spindle 21 downwardly is supported by the roll 43. The reaction driving force tending to move the drive spindle upwardly is resisted by the roll 44.

Due to the tight rolling contact between the spindles and the backing rolls it is important to keep dirt and chips from around the spindles and suitable closure plates coact with the end cap 35 and dust seals 36 for this purpose.

The radially outer tips of the cutter blocks 52 cut and form the side walls of the chambers 53 and when the spindles reach their outer limit of travel the axially outer edges of the cutters face the bottoms of the chambers. With particular attention to Figs. 2 and 6 it will be noted that the shanks of the drill bits 9 and 9A are reduced in diameter behind the cutting diameters of the bits. The cutter blocks 52 extend radially inwardly behind the pe riphery of the bits as at 54 so that the bottoms of the chambers are faced completely to the shaft bores. It should be understood that gear pump bodies are usually cast roughly to size so that the cutters 52 perform only finishing cuts in the body.

Having thus described the invention, what is claimed as new and is desired to be secured by Letters Patent is:

1. A boring machine comprising a base having a slideway, a head slidable on said way, a Work holder positioned to hold the work opposite the end of said head, three spaced journal blocks on said head and having closely spaced sets of alined bearings therein, a drive spindle journaled'in one set of bearings and a counter spindle journaled in the. other set of bearings, means forming a splined driving connection to the inner end of said driving spindle, meshing gears on said spindles locatedbetween the outer and intermediate journal blocks,

ing rolling contact with each other, backing rolls mounted on the outer side of the outer journal block and engaging the opposite sides and diverging sides of said shoulders on said spindles, other backing rolls mounted on the inner side of the outer journal block and engaging the opposite sides of said spindles and the converging side of one spindle and the diverging side of the other spindle, thrust bearings coacting with said spindles, the 'EhlllSt bearing on the counter spindle being adjustable on the head, cutting tools removably mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened'coplanar cutting edges on their radially extending outer edges and on their axially extending radially outer edges, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said blocks, and means for advancing said head on said slideway.

2. A boring machine comprising a base having a slide- Way, a head slidable on said way, a work holder positioned to hold the work opposite the end of 'said. head, spaced journal blocks on said head and having closely spaced sets of alined bearings therein, a drive spindle journaled in one set of bearings and a counter spindle journaled in the other set of bearings, means forming a splined driving connection to the inner end of said driv ing spindle, meshing gears on said spindles located between thev journal blocks, annular shoulders on the outer ends of said spindles having rolling contact with each other, backing rolls mounted on the outer side of the outer journal block and engaging the opposite sides and diverging sides of said shoulders on'said spindles, other backing rolls mounted on the inner .side of the. outer journal block. and engaging the opposite sides of said spindles and the converging side of one spindle and the'driverging side of the other spindle, thrust bearings coacting with said spindles, the thrust bearing on the counter spindle being adjustable on the head, cutting tools removably mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened coplanar cutting edges on their radially extending outer edges, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said blocks, and means for advancing said head on said slideway. 3. A boring machine comprising a base having a slideway, a head slidable on said way, a work holder positioned to hold the work opposite the end of said head,

spaced journal blocks on said head and having closely spaced sets of alined bearings therein,-a. drive spindle journaled in one set of bearings and a counter spindle journaled in the other set of bearings, means forminga driving connection to the inner end of said driving coacting with said spindles, the thrust bearing on the counter spindle being adjustable on the head, cutting tools removably mounted on the'outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened coplanar cutting edges-0n their radially extending axially outer edges, boring bits projecting from the outer ends of said cutting tools and having reduced inner ends with periphery of the bits radially overlapping the coplanar cutting edges of the cutting tools, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said blocks, and means for advancing said head on saidslideway.

4 A boring machine comprising a base having a slideway, a head slidable on said way, a work holder positioned to hold the work opposite the end of said head, spaced journal blocks on said head and having closely spaced sets of alined bearings therein, a drive spindle journaled in one set of bearings and a counter spindle journaled in the other set of bearings, means forming a driving connection to the inner end of said driving spindle, meshing gears on said spindles located between the journal blocks, means on the outer ends of said spindles providing rolling contact between the spindles;

backing rolls mounted on the outer side of the outer journal block and engaging the opposite sides of said spindles, other backing rolls mounted on the inner side of the outer journal block and engaging the opposite sides of said spindles, thrust bearings coacting with said spindles, cutting tools removably mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened coplanar cutting edges on their radially extending axially outer edges, boring bits projecting from the outer ends of said cutting tools and having reduced inner ends with periphery of the bits radially overlapping the coplanar cutting edges of the cutting tools, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said blocks, and means for advancing said head on said slideway.

5. A boring machine comprising a base having a slideway, a head slidable on said way, a work holder positioned to hold the work opposite the end of said head, a journal block on said head and having closely spaced bearings therein, a drive spindle journaled in one bearing and a counter spindle journaled in the other bearing, means forming a driving connection to the inner end of said driving spindle, meshing gears on said spindles located adjacent the inner side of said pournal block, means on the outer ends of said spindles adjacent said block providing rolling contact between the spindles, backing rolls mounted on the outer side of the journal block andengaging the opposite sides and diverging sides of said spindles, other backing rolls mounted on the inner side of the journal block and engaging the opposite sides of said spindles and the converging side of one spindle and the diverging side of the other spindle, thrust bearings coacting with said spindles, cutting tools removably mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened coplanar cutting edges on their radially extending axially outer edges, boring bits having reduced inner ends received in the outer ends of said tool with the cutting edges of the bits spaced axially outwardly from and radially overlapping the cutting edges on said tools, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said block, and means for advancing said head on said slideway.

6. In a boring machine having a base having a slideway and a head slidable on said way and a work holder positioned to hold the Work opposite the end of said head and means for relatively advancing said head and said holder toward each other, a journal block on said head and having closely spaced bearings therein, a drive spindle journaled in one bearing and a counter spindle journaled in the other bearing, means forming a driving connection to the innerend of said driving spindle, meshing gears on said spindles located adjacent the inner side of said journal block, means on said spindles adjacent said block providing rolling contact between the spindles, backing rolls mounted on the outer side of the journal block and engaging the opposite sides of said spindles, other backing rolls mounted on the inner side of the journal block and engaging the opposite sides of said spindles, thrust bearings coacting with said spindles, cutting tools mounted on the outer ends of said spindles, said tools having radially extending and inter-meshing arms t? with hardened coplanar cutting edges on their radially extending axially outer edges, and boring bits having'reduced inner ends received in the outer ends of said tool with the cutting edges of the bits spaced axially outwardly from and radially overlapping the cutting edges on saidtools, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported in said block.

7. In a boring machine having a head and a work holder positioned to hold the work opposite the end of said head and means for relatively advancing said head and said holder toward each other, spaced journal blocks on said'head and having closely spaced sets of alined bearings therein, a drive spindle journaled in one set of bearings and a counter spindle journaled in the other set of bearings, means forming a driving connec tion to said driving spindle, meshing gears on said spindles located between the journal blocks, means on the outer ends of said spindles providing rolling contact between the spindles, backing rolls mounted on the outer side of the outer journal block and engaging'the opposite sides and diverging sides of said spindles, thrust bearings coacting with said spindles, and cutting tools removably mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with hardened coplanar cutting edges on'their radially extending axially outer edges, said rollers being mounted on bearings positioned eccentrically on pins rotatably adjustably supported on said block.

8. In a boring machine having a head and a work holder positioned to hold the work opposite the end of said head and means for relatively advancing said head and said holder toward each other, a journal block on said head and having closely spaced bearings therein, a drive spindle journaled in one bearing and a counter spindle journaled in the other bearing, means forming a driving connection to said driving spindle, meshing gears on said spindles, means on said spindles providing rolling contact between the spindles, backing rolls mounted on the journal block and engaging the opposite sides ofsaid spindles, thrust bearings coacting with said spindles, and cutting tools mounted on the outer ends of said spindles, said tools having radially extending and intermeshing arms with coplanar'cutting edges on their radially extending axially outer edges, said rollers being adjustably supported in said block.

9. A machine for simultaneously boring intersecting holes comprising parallel spindles having rolling contact adjacent their working ends, cutters removably mounted on the working ends of said spindles and having radially extending intermeshing arms with coplanar cutting edges on their axially outer ends, pilot bits projecting from the ends of said cutters, said bits being reduced at their inner ends and projecting radially at their outer ends in radially overlapping relation to the inner ends of said cutting ,edges, bearings supporting said spindles, backing roll members supportingly engaging said spindles opposite the area of rolling contact therebetween and on the diverging sides of said spindles, said backing members being adjustable radially of said spindles, and means for simultaneously driving said spindles including meshing gears on the spindles and a driving connection to one spindle.

10. A machine for simultaneously boring intersecting holescomprising parallel spindles having rolling contact adjacent their working ends, cutters mounted on the working ends of said spindles and having radially extending intermeshing arms with coplanar cutting edges on their axially outer ends, pilot bits projecting from the ends of said cutters, said bits being reduced at their inner ends and projecting radially at their outer ends in radially overlapping relation to the inner ends of said cutting edges, bearings supporting said spindles, backing roll members supportingly engaging said spindles opposite the area of rolling contact therebetween, said backing memt 7 hers being adjustable radially of said spindles, and means for simultaneously driving said spindles.

11. A machine for simultaneously boring intersecting,

holes comprising parallel spindles having rolling contact adjacent their working ends, cutters removably mounted on the working ends of said spindles and having radially extending intermeshing. arms with cutting edges on their axially outer ends, bearings supporting said spindles, backing roll members supportingly engaging said spindles to oppose side thrust forces created therein by action of said cutters, said backing members being adjustable radially of said spindles, and means for simultaneously driving said spindles including meshing gears on the spindles and a driving connection to one spindle.

12. A machine for simultaneously boring intersecting holes comprising parallel spindles having rolling contact adjacent their working ends, cutters removably mounted on the working ends of said spindles and having radially extending intermeshing arms with cutting edges on their axially outer ends, bearings supporting said spindles, backing roll members supportingly engaging said spindles to I oppose side thrust forces created therein by action of said cutters, and means for simultaneously driving said spindles including meshing gears on the spindles and a driving connection to one spindle.

13. A machine for simultaneously boring intersecting holes comprising parallel spindles having rolling contact adjacent their working ends, cutters mounted on the 8 working ends of said spindles and having radially extending intermeshing arms with cutting edges on their axially outer ends, bearings supporting said spindles, backing roll members supportingly engaging said spindles opposite the area of rolling contact therebetween, said backing members being adjustable radially of said spindles, and means for simultaneously driving said spindles.

14. A machine for simultaneously boring intersecting holes comprising closely adjacent spindles, means on said spindles providing rolling contact adjacent their working ends, cutters mounted on said spindles and having radially extending intermeshing arms with cutting edges on their axially outer ends, bearings supporting said spindles, back ing members supportingly engaging said spindles opposite the area of rolling contact therebetween, and means for simultaneously driving said spindles. I

, References (Iited in the file of this patent UNITED STATES PATENTS