US2452989A

US2452989A - Cam grinding machine

Info

Publication number: US2452989A
Application number: US514806A
Authority: US
Inventors: Harry W Brown
Original assignee: National Acme Co
Current assignee: Devlieg Bullard Inc
Priority date: 1943-12-18
Filing date: 1943-12-18
Publication date: 1948-11-02
Anticipated expiration: 1965-11-02

Description

l Nov. 2, 194s.

H. w. BRowN GAI @BINDING MACHINE 6 Sheets-Sheet 1 Filed Dec. 18, 1943 Nov. 2, 1948. i I H. w. BRowN 2,452,989

l cAu @BINDING MACHINE Filed Dec, 18, 1943 6 sheets-sheet 2 H. w. BROWN cm @alumna uAcHINE Nov'. z, 194s.

6 Sheds-Sheet 3 Filed Dec.' 1s. 1945 I I I I I I Nov. 2, 1948. Hjw. BRowN I CAM GRINDING MACHINE e sheets-sheet 4 Fnd nec. 1a. 194s Nov. 2, 1948. H. w. BROWN l 2,452,989

cm GRINDING MACHINE Filed Dec. 1a, 1945 e sheets-sheet e Patented Nov. 2, 1948 UNITED STATES PATENT ori-ICE f 2.45am i CAM GamnlNGvMAcnma Harry W. Brown, Cleveland, Ohio, asignor to The National Acme Company, Cleveland, Ohio, a corporation of Ohio l .application December is, 194s, serial No. 514,806

(Cl. 51-10l)4 13 Claims.

This invention relatesto machines for grinding internal and external cams and `more particularly to what are known as accelerating` cam grinding machines, the principal object being the provision of a machine capable of grinding multiple cam surfaces on either the inner or outer peripheral surface of a work piece such as a die cup for dies.

A further object of the present invention is the provision of a cam grinding machine provided with a reciprocal table having a very slight movement of as little as 1%" with a very rapid back and forth motion.

A further object of the invention is the provision of means for rotating the work holding table to permit the grinding of tapered cam surfaces.

A still further object of the invention is the provision oi. a reciprocating table adapted to move the grinding tool at right angles to the reciproeating movement of the work holding table.

A still further object of the invention is the g provision of means for rotating the spindle of the work holding head in which provision is made for changing the ratio of rotation of the work holding means relative to the master cam in order to grind a variable number of cam surfaces.'

A still further object oi the invention is the provision of hydraulic or fluid means for operating many of the parts of the machine in proper timed relation.. i

A still further'obiect of the invention is the provision of such a' machine that will be simple in construction, emclent and highly accurate in use and, at the same time, comparatively inexpensive to manufacture.

In the drawings accompanying and forming a part of this specification,

Fig. 1 is a side elevation of this improved machine.

Fig. 2 is a view of one end of the machine taken at right angles to Fig. 1. l

Fig. 3 is a view taken on line 3 3 of Fig. 7.

Fig. 4 is a view of the opposite end of the machine to that shown in Fig. 2 and illustrates the gearing for rotating the work at variable speeds.

Fig. 5 is a detail of the operating handle and its shock absorbing means.

Fig. 6 is adetail of the operating handle taken at right angles to Fig. 5. e l

Fig. 'I is a llongitudinal section through the work carrying head somewhat enlarged and showing the spindle connection with the driving means and the manner in which the head may be rotated for grinding angular surfaces.

2 Fig. 8 is an enlarged detail view showing the master cam and its associated parts for oper- 4 tion and mode of operation thereof, I desire to lli have it understood that the invention is not limited to the details o! construction and arrangement of parts illustrated in the accompanying drawings since the invention is capable oi' other embodiments, and that the phraseology employed is for the purpose oi description and not of limitation;

The present machine comprises in general a base or frame 2 of any suitable size and shape housing the Variousmarts of thehydraulic or fluid operating mechanism. Upon this 'base is mounted a shiftable or reciprocal table having secured thereto in any suitable manner a work holding head t and supported on the frame 2 at one end thereof is a rotatable tool holding member l5 suitably carried for reciprocal movement transversely of the table i.

For a-better understanding of the machine, the operation and structure of the various parts will be described separately.

The driving and controlling means for the table 3 in the present instance is hydraulically controlled by means of a double-acting hydraulic pump A. This pump receives fluid from a reservoir 6 by means'of the suction line Y and is suitably driven from a 'motor 'l connected tothe pump by a belt 8 and pulley wheel `9. y

This double pump is provided with a high pressure low volume line R. leading from the high f pressure side of the pump running through a tiow control valve P to a four-way pilot valve B and then to either end of a cylinder I0 attached to the under side of the table 3. The course oi.' the fluid at each end of the cylinder is indicated by arrows and it will thus be seen that the passage to either end of the cylinder i0 will cause the cylinder'housing il to be shifted either to the right or left and with it the table 3 and work holding head ii will be reciprocated at any desirled stroke or speed controlled by the flow control va ve P.

A spring pressed lever i2 is provided at the front of the base of the machine and when this 3 lever is pressed in, (see Fig. 6) the machine is started and when it is pulled out the machine is stbDDed.\ When in its engaged` position (inward) the lever I2 is adapted to be engaged by adjustable dogs or lugs 'I3 suitablyfastened to the `side of the slide 3 and contact with these dogs i 3 will cause the lever I2 to be rocked sideways to the left and right. The opposite end of the lever I2 is connected by means of linkage Il to a pilot valve E which is connected through the line S to the low pressure high volume side of the pump A and to the four-way'pilot valve B to control the direction of movement of the table 3 and head I. On certain classes of work, the stroke or reciprocating movement of the table has to be very short and this machine permits this stroke to be as short as 135" and shock to the valve which would ordinarily result from such a short stroke when reciprocating at high speed is prevented by means of the spring E. l The work holding head 4 carried by this reciprocatlng table 3 is provided with a rotatable -spindle I5 having at one end 4thereof a chuck or 4. To eliminate any backlash of the gears, in

view of the train of gears required, a spring tension brake 22 (see Figs. l, 3 and 7) is provided on the end of the spindle and this brake prevents any backlash or lost motion.

In the particular structure illustrated, the machine is designed to grind four cam surfaces on the inner periphery of a work piece and the gearing I3, I9, 29 and 2| ls so constructed and proportioned that* the spindle I5 will be rotated at the proper speed for the grinding of four cam surfaces. However, should it be desired to grind a greater or lesser number of cam surfaces, provision has been made to vary the speed of rotation of the spindle 5 as may be deemed necessary.

Intermediate the gear train I9, a swinging arm 23 is provided and by merely changing the position of this arm and substituting the proper gear, the

' speed of the spindle I5 may be changed. The

ratio of speed of this spindle to the speed of the master cam hereinafter to be described must Aat all times be relative.

Since the cams have to be ground in variousl shapes, length of grooves, taper or straight, an adjustable work holding head has been provided so that this head may be set at any desired horizontal angle relative to the grinding tool. For that reason, the bevel gear box 25 and bevel gear drive 29, 2i is built in such manner that the work vholding head d may be rotated at any angle relative to the tool for `diiferent'classes of work without affecting the drive 'of the work spindle I5. It will be noted that the swinging or rotating of the housing 4 on the table 3 will cause the gear 2i to rotate around its meshing bevel gear of the train 20.

Located at one end of the machine is the 'grinder unit 5 having a rotatable spindle 25 car- A and may be directly connected thereto or connected by means of a belt 29, as illustrated.

This grinder unit 5 ls mounted on across sliding table 29 adapted to reciprocate transversely of the table 3. A suitable manually operated wheel 30 provided with a section 3| having graduations thereon is fixed to a shaft 32 which is in turn connected by means of gearing 33 to a may -be obtained by the proper selection lof' gearing.

Mounted on the opposite end of this cam shaft is the master cam 36 and this cam engages a roller 31 of a roller holding latch or lever 33 pivotally connected or fastened by means of a stud 39 to the frame of the machine in such manner that the pivot peint will always bear the same fixed relation to the cam shaft 35.

The transverse slide or table 29 is provided with a vertically positioned T-slot 90 for the reception of a block 4I contacting the lever 38 and this block may be moved up or down in such manner that its position, together with the movement of the pivoted lever 38 by the cam 36, will limit or control the reciprocating stroke of the table 29.

The complete operation of the machine and the relationship of the various parts will now be described.

A work piece, as i 1, to be ground with four cam surfaces is inserted in the chuck or holding means I6 and the tool carrier 5 is provided with the necessary grinding tool and properly positioned by the manually operative Wheel 30.

Thereupon the motor 21 is started to start the grinding tool rotating at a very high speed. The hydraulic mechanism is then started to cause fluid to be supplied to reciprocate the work table 3 and the lever I2 is pressed into engagement to control operation of the pilot valve E to control the direction of flow of the fluid so that the table will be shifted back and forth.'

During these operations, the motor F is started Ibv means of the hand controlled valve D to effect rotation of the gear trains i3 et seq. and thereby the work spindle I5 and also the cam shaft 35 and cam 36. The gearing illustrated is such that the cam 86 will be rotated at four times the speed of the work spindle I5 so that the tool may grind the four desired cam surfaces by reciprocating the transverse tool table or slide 29 four times to each rotation of the work and during the entire operation of the machine, the` work table 3 is reciprocated back and forth at a very high rate of speed to insure an even grinding of the cam surfaces.

From the foregoing it will be understood that while I have described the reciprocation of the work table in one direction with the tool slide reciprocating transversely thereto, 'these movements may be reversed if desired or one table may have a'dual reciprocation while the other. remained in a fixed position.

It is to be understood that by describing in detall herein any particular form, structure or y it may be made, or all or the modes oi its use, I claim:

`1. A cam grinding machine having a reciprocating work carrier rotatable about its longitudinal axis for varying the angle of the work, means lfor rapidly reciprocating said carrier, a rotata-ble work spindle carried by said carrier, means ior rotating said spindle, a reciprocating tool carfrier reciprocal transversely of said work carrier,

means for reciprocating it, a rotatable. spindle carried by said tool carrier, means for rotating it, and means for adjusting the position of said tool carrier transversely of said work carrier.

ll .f6 l said carriersv reciprocating at a speed ratio relative to the speed oi rotation of the spindle of the other, said reciprocating means including fluid valve operating means for controlling the 2. A cam grinding machine having a reciprocat- I lng work carrier rotatable about its longitudinal axis for varying the angle of the work, means for rapidly reciprocating said carrier, a rotatable work spindle carried by said carrier, means for rotating said spindle, a reciprocating tool carrier reciprocal transversely of said work carrier, means for reciprocating it, said last means including a cam rotated by the work spindle rotating means, a rotatable'splndle carried by said tool carrier, and means for rotating it.

3. A cam grinding machine having a reciprocating work carrier rotatable about its longitudinal axis for varying the angle of the work, means for rapidly reciprocating said carrier, a rotatable work spindle carried by said carrier,

tool carrier reciprocal transversely of said work carrier, means for reciprocating it, said last means including a cam rotated by the work spindle rotating means, means for rotating said cam at a speed ratio relative to the speed of rotation of said spindle, a rotatable spindle carried by said tool carrier, and means for rotating it.

d. A cam grinding machine having a reciprocating work carrier rotatable about its longitudinal axis for varying the angle of the work, means for rapidly reciprocating said carrier, a. rotatable work spindle carried bysaid carrier, means for rotating said spindle, a reciprocating tool carrier reciprocal transversely of said work carrier, means for reciprocating it, said last means including a cam rotated by the work spindle rotating means, means for rotating said cam at a speed ratio relative to the speed of rotation of said spindle, means for varying said speed ratio, a rotatable spindle carried by said tool carrier, and means or rotating it.

5. A cam grinding machine having apair of carriers each provided with a rotatable spindle, one carrying a work piece having a cam to be lmeans for rotating said spindle, a'reciprocating stroke ofthe high speed carrier, and means `for preventing shock to said iluid valve operating means.

7. A cam grinding machine having a pair of carriers each provided with a rotatable spindle, one carrying a work piece having a cam to be ground and the other a cam grinding tool, and reciprocal transversely of each other, means for reciprocating one carrier at high-seed, one of said carriers reciprocating at a, speed ratio relative to the speed of rotation oi the spindle of the other, said reciprocating means including uid valveoperating means for controlling the stroke of the high speed carrier, means for preventing shock to said iluid valve operating meanaand means for changing the relation of said speed ratio.

8. A cam grinding machine having a reciprocating work carrier rotatable about its longi` .tudinal axis for varying the angle of the work, iluid means for rapidly reciprocating said carrier, means for controlling the stroke oi.' said reciprocating carrier, means for preventing shock` to said iluid means, a rotatable spindle carried by said carrier, fluid means for rotating said spindle, means for changing the speed of rotation of said spindle, a reciprocating tool carrier reciprocal transversely of said work carrier, fluid means for reciprocating it, means for controlling the stroke of said last reciprocating carrier, means for controlling the speed of reciprocation thereof, means for adjusting theposition of said last carrier, a. rotatable spindle carried by said last carrier, and means for rotating it.

9. The machine of claim 8 in which the means for reciprocating the tool unit includes a rotating cam.

- 10. The machine of claim 8 in which the means for reciprocating the tool unit includes a rotating cam so connected with the rotatable work spindle operating means that the work spindle and cam will rotate at different relative speeds. 1l. A cam grindingmachine comprising a reciprocating table, fluid controlled means ior reciprocating said table, iluid valve operated means for controlling the stroke of the table., a work holder carried by the table, a rotary spindle carried by said work holder, means for rotating said spindle, a reciprocating tool unit, means for addusting it, cam means for reciprocating it and ground and the other a cam grinding tool, and

reciprocal transversely of each other, means for reciprocating one carrier at high speed, said having connection with the means for rotating the work spindle and at predetermined speed ratio relative thereto, and means 'cooperating with said cam means for controlling the stroke of the reciprocating tool unit.

12. A cam grinding machine having a reciprocating work carrier, iluid means for rapidly reciprocating said carrier, a rotatable work spindle carried by said carrier, iluid means for rotating said spindle, a, .reciprocating tool carrier reciprocal transversely of said work carrier, iluid means for reciprocating it and including cam operated means connected with the rotary work spindle operating. means, a rotatable spindle carried by said tool carrier, means for operating it, and means cooperating with said cam operated means for controlling the stroke of the tool umts 13. A cam grinding machine comprising a reciprocating table, uid controlled means for reciprocating said table, uid valve operated means e spindle and at a, predetermined speed ratio rel ative thereto.

l HARRY W. BROWN.

REFERENCES CITED The following references are of record in the -le of this patent:

UNITED STATES PATENTS Name Date Whitney Dec. 11, 1917 Number Number 8 Name Date Van Norman -e Oct. 27, 1925 vTessky Oct. 30, 1928 Braren Aug. 4, 1931 Scharf! Aug. 30, 1932 Olson Mar. 21, 1933 Olson f Nov. 7, 1933 Sassen Aug. 4, 1936 Amidon Dec. 7, 1937 IMaglott Aug. 23, 1938 Bickel Jan. 10, 1939 Flanders Jan. 16, 1940 Aller et al.v Jan. 23, 1940 'Rybicky July 1 1941 Mossdori' Dec. 23, 1941 Turrettini Mar. 10, 1942 Herrmann May 26, 1942 4Atherholi: et al. June 15, 1943 Horton May 30, 1944