US3822689A

US3822689A - Side dressing device

Info

Publication number: US3822689A
Application number: US00338270A
Authority: US
Inventors: S Oshima
Original assignee: Toyoda Koki KK
Current assignee: Toyoda Koki KK
Priority date: 1972-03-08
Filing date: 1973-03-05
Publication date: 1974-07-09
Anticipated expiration: 1991-07-09
Also published as: FR2178599A5; JPS48105189U; AU461927B2; JPS5141275Y2; AU5297373A

Abstract

A side-dressing device for grinding wheels comprising a carriage which makes a reciprocating slide motion relative to the body of the dressing device; a pair of main shafts attached to said carriage and rotatable relative to said carriage; shafts rotatable within said main shafts, set eccentrically to the axis of said main shafts and fitted with a rotary diamond truing cutter at their respective outer ends; and a drive mechanism for rotating said rotatable shafts in opposite directions to each other; said pair of rotary diamond truing cutters being so arranged that they may reciprocate and slide on each side surface of a grinding wheel to be dressed which is being rotated at a fixed position on the wheel slide. Said main shafts being externally fitted with gears, which mesh with gears which are linked with the feed shaft to cause the former gears to rotate in opposite directions; and said feed shaft being turned by a certain angle so that the rotary diamond truing cutter may be brought up to the grinding wheel.

Description

[451 July 9,1974

United States Patent 1191 Oshima erHarold D. Whitehead Primary Examin Susumu Oshima Okazaki Japan Attorney, Agent, or Fzrm-Hutch1nson & Milans E C w E D G m m m En w v Sh x mfl UH.

[57] ABSTRACT A side-dressing device for grinding wheels comprising a carriage which makes a reciprocating slide motion relative to the body of the dressing device; a pair of [73] Assignee: Toyoda Koki Kabushiki Kaisha, Kariya, Aichi Perfecture, Japan Mar. 5, 1973 [22] Filed:

main shafts attached to said carriage and rotatable rel- [21 1 Appl 338270 ative to said carriage; shafts rotatable within said main shafts, set eccentrically to the axis of said main shafts and fitted with a rotary diamond truing cutter at their 4128270 respective outer ends; and a drive mechanism for rotating said rotatable shafts in opposite directions to each other; said pair of rotary diamond truing cutters ed h b an O t d e h being so arranged that they may reciprocate an on each side surface of a grinding w which is being rotated at a fixed position on the wheel slide. Said main shafts being externally gears, which mesh with gears which are linked with the feed shaft to cause the former gears to rotate in opposite directions; and said feed sh UNITED STATES PATENTS aft being turned l 5 by a certain angle so that the rotary diamond truing 125;} 1 CD cutter may be brought up to the grinding wheel.

Benicke Kikuchi 722 I1 999 ll]: 778

4 Claims, 5 Drawing Figures aw/Ar 1 SIDE DRESSING DEVICE BACKGROUND OF THE INVENTION The present invention relates to a side-dressing device for dressing the sides of a grinding wheel.

In the case of a conventional dressing device for dressing both sides of a grinding wheel which is equipped with a single point diamond dresser mounted on the arbor fixed to the chucks for successive dressing of both sides of a grinding wheel, one grinding wheel has to be dressed in two steps, which results in poor working efficiency. Moreover, in this type of device the feeding of said dresser has to be manually adjusted. Such a practice is inefficient, needs a relatively high degree of skill for maintaining precision, and it involves a hazard to the workers hands coming into contact with a running grinding wheel.

SUMMARY OF THE INVENTION The primary object of the present invention-is to provide a side-dressing device which utilizes a pair of rotary diamond truing cutters which slide and reciprocate in a definite manner and direction on each side surface of a grinding wheel, thereby effecting simultaneous dressing of both sides of the grinding wheel.

Another object of the present invention is to provide a side-dressing device which has an automatic adjustment of the feeding of the rotary diamond truing cutters by bringing said diamond truing cutters up to the grinding wheel through a reciprocating slide motion of said diamond truing cutters.

Still another object of the present invention is to pro vide a side-dressing device which is equipped with a means for adjusting the feed of the rotary diamond truing cutter, which assures a desired feed of the same.

Still another object of the present invention is to provide a side-dressing device in which the feed of the rotary diamond truing cutter is adjusted by a screw means, the engagement of said screw means being biased in one direction by a spring means, thereby eliminating any backlash in said screw means and ensuring high precision in the feed adjustment.

Other objects of the present invention will become apparent from the following account of an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, showing mainly a longitudinal section of the drive mechanism for the rotary diamond truing cutters 1, 1 having their peripheral end faces covered with diamonds, the carriage 2, which is vertically slidable, is

provided with two cylindrical main shafts 3, 3 whichare rotatable in relation to said carriage 2. Within said main shafts 3, 3 are transmission shafts 4, 4 which are rotatably mounted therein and which are concentric with said main shafts 3, 3 and the

rotatable shafts

5, 5 are rotatably and eccentrically mounted within the main shafts 3, 3 so that they are able to be moved into contact with the grinding wheel 34 from the axis of said main shafts 3, 3. The lower part of said transmission shafts 4, 4 and the upper part of said

rotatable shafts

5, 5 are coupled together by means of a universal joint connection 6. At the lower ends of said

rotatable shafts

5, 5 the rotary diamond truing cutters l, 1 are mounted and fixed thereto and are made to rotate in opposite directions to each other. For this purpose, the drive shaft 8 of the motor 7 fitted at the top of the carriage 2 is provided with a pulley 10 which is integrated with a drive gear 9 and this pulley 10 is connected via a belt 12 to a pulley 11 provided at the upper end of one transmission shaft 4. A pulley 13, is provided at the upper end of the other transmission shaft 4, and is connected via a belt 16 to a pulley 15 which is integrated with an intermediate gear 14 meshing with said drive gear 9, so that the rotary diamond truing cutters l, 1 will be rotated in opposite directions to each other when the drive shaft 8 is driven by the motor 7.

Explanation of the vertical sliding mechanism of the movable table 2 will now be given. The carriage 2 is slidably mounted on the sliding surface of the dovetail groove 19 in the body 18 of the dressing device fixed to thewheel slide 17, as illustrated in FIG. 2, while the body 18 of the dressing device itself is provided with a cylinder 20. As seen from FIG. 3, said cylinder 20 has its piston 21 fitted to the connecting rod 22, the upper end of which is fixed to the flange 23 of said carriage 2, whereby said carriage 2 can be vertically moved by pressurized oil charged into and discharged out of said Meanwhile, there is provided a means for locking the body 18 of the dressing device and the carriage 2 when the magnetic change-over valve 26 is set in a closed state as illustrated in FIG. 3. This locking means is constructed such that the locking rod 31 in the body 18 of the dressing device may fit into the notched groove 30 cut on the movable table 2, as illustrated in FIG. 2. When the carriage 2 is vertically displaced, pressurized oil is introduced into the oil path 32, thereby locking rod 31 is made to recede and overcome the force of the compressive spring 33. When the carriage 2 is halted at the topmost position, the pressurized oil is discharged out of the oil path 32, thereby the compressive spring 33 will act to move the locking rod 31 downwardly to fit into the notched groove 30 and thus locking the body 18 of the dressing device and the carriage 2. The action of said locking means is interlocked with that of the magnetic change-over valve 26 illustrated in FIG. 3.

Both sides of the grinding wheel 34 to be dressed as shown in FIG. 1 can be dressed through the above described vertical displacement of the carriage 2 and the rotation of the rotary diamond truing cutters l, 1. The grinding wheel 34 to be dressed is fitted rotatably at a definite position of the wheel slide 17 and this grinding wheel 34 can rotate while being dressed.

The main shafts 3, 3 are concentrically fitted with

external gear wheels

37, 37 which turn said main shafts 3, 3 to adjust the gap between the rotary diamond truing cutters I, l, i. e., the feed of the grinding wheel 34 to be dressed. This feed adjusting means is illustrated in FIGS. 2, 4 and 5.

The

gear wheels

37, 37 mesh with the

worm gears

39, 39 which are integrated with the

feed shafts

38, 38. When the set

screws

41, 41 ofthe coupling 40 are tightened, the two

feed shafts

38, 38 are coupled together, and when these set

screws

41, 41 are loosened, said

shafts

38, 38 can separately turn. The

worm gears

39, 39 are twisted in opposite directions to each other, so that when said

feed shafts

38, 38 coupled together by the coupling 40 are turned, the main shafts 3, 3 will rtate in opposite directions to each other.

Meanwhile, the

gear wheels

37, 37 on the opposite side to the

worm gears

39, 39 mesh with the

worm gears

42, 42 for eliminating the backlash between the

worm gears

39, 39 and the

gear wheels

37, 37. These backlash-eliminating

worm gears

42, 42 give the

gear wheels

37, 37 the ability to turn in a definite direction and for this purpose, a compressive spring 43 is inserted between these

worm gears

42, 42 which are movable in the axial direction.

Thus, the

gear wheels

37, 37 and the

worm gears

39, 39 meet on the same tooth surface, thereby eliminating the backlash. These backlash-eliminating

worm gears

42, 42 should be long enough not to allow disengagemerit within the turning angle of the

gear wheels

37, 37 which turn in accordance with the adjusted distance between the rotary diamond truing cutters l, 1.

The

feed shafts

38, 38 can be rotated by suitable hand wheels 44, 44- fixed to the

feed shafts

38, 38. Also, the

feed shafts

38, 38 may be automatically rotated by an automatic feed device, thereby rotating the main shafts 3, 3. For this purpose, the right feed shaft 38 in FIG. 2 is fitted with a ratchet wheel 45 and with a swing plate 46 which is rotatably mounted on the feed shaft 38 and the ratchet wheel 45 engages a ratchet pawl 47 pivotally mounted on the swing plate 46. This ratchet pawl 47 is urged by a spring (not shown) toward the periphery of the ratchet wheel 45 so as to engage the ratchet wheel 45 at all times. The ratchet pawl 47 pivoted to the swing plate 46 can rotate the ratchet wheel 45 engaged therewith and accordingly, the feed shaft 38 also, only when the swing plate 46 is rotated in the arrow direction as shown in FIG. 4. When, however, the swing plate 46 is rotated in the opposite direction to the arrow, the swing plate 46 alone will rotate since the ratchet pawl 47 slips on the ratchet wheel 45 without causing the ratchet wheel 45 to rotate. The rod 51 of the piston 50 which fits into the feeding cylinder 49 contacts the projecting side 48 of the swing plate 46, and when the magnetic change-over valve 52 is ener gized, the rod 51 is moved to the left extending out of the feeding cylinder 49 to push the swing plate 46, thereby rotating the ratchet wheel 45 in the arrow di rection. When the ratchet wheel 45 rotates in the arrow direction, the

feed shafts

38, 38 integrated with the ratchet wheel 45 also rotate, thereby rotating the left main shaft 3 clockwise and the right main shaft 3 counterclockwise via the

worms

39, 39 and the

gear wheels

37, 37 in FIG. 2 and as a result, narrowing the gap between the rotating

shafts

5, 5 and accordingly the gap between the rotary diamond truing cutters l, 1.

When the magnetic change-over valve 52 is deenergized, the compressive spring 53 provided within the feeding cylinder 49 resets the piston and its rod St to the original position, while at the same time the tensile spring 54 resets the swing plate 46 to the original position.

The electromagnetic switch valve 52 has to be interlocked with the movement of the carriage 2 so that said valve 52 may be energized when the carriage 2 rises to cause the grinding wheel 34 to be dressed and the rotary diamond truing cutters l, 1 to get out of contact with each other; and it may be deenergized, while the dressing is going on with the carriage 2 falling or while the dressing is going on with the carriage 2 rising or slightly before said valve 52 is energized. In one embodiment of the invention, the magnetic change-over valve 52 can be operated by means of the

limit switches

27, 28 which engage the flange 23 of the carriage 2. The upper limit switch 27, which is actuated by the rising end of the carriage 2, energizes the switch valve 52 and thereby the gap between the rotary diamond truing cutter wheels 1, I is narrowed. Subsequently, the lower limit switch 28, which is actuated by the falling end of the movable table 2, de-energizes the change-over valve 52. Thus, the swing plate 46 is reset in readiness for the next feeding and the rotary diamond truing cutters l, 1 can be successively fed to the grinding wheel 34 to be dressed. In FIG. 4, numeral 55 designates a stop for resetting the rotating angle of the swing plate 46 to adjust the amount of one feed; and numeral 56 indicates a pull piece for disengaging the ratchet wheel 45 and the ratchet pawl 47 when the feed shaft 38 is to be rotated by the hand wheel 44 for adjusting the feed.

As indicated in FIGS. 1 and 5, at the top of the main shafts 3, 3 there is provided a means for checking the end of dressing as well as for setting the rotating angle of the main shafts 3, 3, i.e., the ultimate feed amount of the rotary diamond truing cutters l, 1. This means can be set in position by fitting

bolts

57, 57 projecting at the top of the main shafts 3, 3 into the

arcuate slots

59, 59 provided on the turning plate 58 and turning this turning plate 58 within the range of angles along said

arcuate slots

59, 59. Meanwhile, there are nuts 60, 60 screwed to the

bolts

57, 57, and by tightening said nuts 60, 60 the main shaft 3 and the turning plate 58 can be immobilized in an arbitrary position. The edge of said turning plate 58 is equipped with a dog 62 which bears against a stop 61 fitted to the carriage 2. A jet orifice 64 opens in the stop 61 fitted to the carriage 2 so that pressurized air supplied through the throttle valve 63 can be ejected out of said orifice 64. When the turning plate 58, fitted to the main shaft 3, turns in the direction of the arrow as seen in FIG. 5 together with the main shaft 3 to make the dog 62 bear against the stop 61, the outlet to the pressurized air ejected out of the orifice 64 of the stop 61 through the throttle valve 63 is blocked and the pressure switch 65 acts to prevent the turning of the plate 58 and accordingly of the main shaft 3.

Therefore, by immobilizing the turning plate 58 with the main shaft 3 in an adequate position, the ultimate feed of the rotary diamond truing Cutters 1, I can be set. Though the electrical control circuit for this purpose is omitted here, it is so arranged that after the dog 62 closes the orifice 64 to thereby actuate the pressure switch 65, the grinding wheel 34 is dressed to a set degree through the final vertical movement of the carriage 2. When the predetermined degree of dressing is finished and the carriage 2 reaches the topmost position, the change-over valve 26 of the cylinder for vertically moving the carriage 2 is closed, the body 18 of the dressing device and the carriage 2 are then locked by fitting the locking rod 31 of the locking device to interlock with this valve 26 into the notched groove 30; and then the motor 7 is cut off. This dressing end confirming means is furnished on both of the main shafts 3, 3; but when the

feed shafts

38, 38 are coupled together by the coupling 40 shown in FIG. 2, and both sides of the grinding wheel are dressed simultaneously by the rotary diamond truing cutters l, 1 in principle, only one such confirming means has to be set. Thus, by loosening the

set screws

41, 41 of the coupling 40, the

feed shafts

38, 38 can be rotated separately and thereby each confirming means can be applied in dressing one side after another or a single side alone.

Such being the composition of the present invention, both sides of a grinding wheel 34 can be automatically dressed to a predetermined degree by rotating the grinding wheel 34 placed in position on the wheel slide 17, running the motor 7 and at the same time, vertically moving the carriage 2. The advantage of the device according to the present invention over the conventional device is as follows: both sides of a grinding wheel can be simultaneously dressed by a pair of rotary diamond truing cutters; the feed of the rotary diamond truing cutters can be adjusted automatically with high accuracy by the above-described simple mechanism; and thus the operation can be efficient and safe with no likelihood of the workers hands coming into contact with a rotating grinding wheel, as in the conventional devices of the prior art.

I claim:

1. A side-dressing device for grinding wheels comprising:

l. a carriage mounted for reciprocatingly sliding movement relative to the body of the dressing device;

2. a pair of main shafts provided on said carriage and mounted for turning movement relative to said carriage;

3. rotatable shafts each being freely rotatable relative to said respective main shafts and positioned within said main shafts and being eccentrically mounted in relationship to the axis of said main shafts, rotary diamond truing cutters being mounted at the outer ends of said rotatable eccentrically mounted shafts with the grinding wheel to be dressed being positioned between said rotary diamond truing cutters;

4. a drive mechanism for rotating said pair of rotatable eccentrically mounted shafts in opposite directions to each other; and

5. an automatic feeding device for applying said pair of rotary diamond truing cutters to said grinding wheel by a turning movement of said main shafts responsive to a reciprocating slide motion of said pair of rotary diamond truing cutters with said carriage.

2. A side-dressing device according to claim 1, wherein said main shafts have gears fitted on their external surfaces and said gears are made to mesh with gears which are connected to feed shafts for rotating said former gears of said main shafts in opposite directions to each other, while at the same time, said feed means rotates said feed shafts through a definite angle.

3. A side-dressing device according to claim 1, wherein said feed means comprises a swing plate, a ratchet wheel fitted to a feed shaft, a ratchet pawl provided on said swing plate and engaging said ratchet wheel, and a piston interlocked with reciprocating slide motion of rotary diamond truing cutters to rotate said swing plate in a definite direction and to rotate said feed shaft by a preset angle through engagement of said ratchet wheel and ratchet pawl.

4. A side-dressing device according to claim 2, wherein a backlash-eliminating means is furnished which at all times urges the gear fitted to said main shaft to rotate in a definite direction.

Claims

1. A side-dressing device for grinding wheels comprising: 1. a carriage mounted for reciprocatingly sliding movement relative to the body of the dressing device; 2. a pair of main shafts provided on said carriage and mounted for turning movement relative to said carriage; 3. rotatable shafts each being freely rotatable relative to said respective main shafts and positioned within said main shafts and being eccentrically mounted in relationship to the axis of said main shafts, rotary diamond truing cutters being mounted at the outer ends of said rotatable eccentrically mounted shafts with the grinding wheel to be dressed being positioned between said rotary diamond truing cutters; 4. a drive mechanism for rotating said pair of rotatable eccentrically mounted shafts in opposite directions to each other; and 5. an automatic feeding device for applying said pair of rotary diamond truing cutters to said grinding wheel by a turning movement of said main shafts responsive to a reciprocating slide motion of said pair of rotary diamond truing cutters with said carriage.