US2870467A

US2870467A - Power brushing machines

Info

Publication number: US2870467A
Application number: US495951A
Authority: US
Inventors: Grosz Emil
Original assignee: ELGRO MACHINE TOOL Co Ltd
Current assignee: ELGRO MACHINE TOOL Co Ltd
Priority date: 1955-03-22
Filing date: 1955-03-22
Publication date: 1959-01-27
Anticipated expiration: 1976-01-27

Description

E. GROSZ POWER BRUSHING MACHINES Jan. 27, 1959 3 Sheets-Sheet 1 Filed. March 22,v 1955 ATTDKMEYS Jan. 27, 1959 E. GROSZ I POWER BRUSHING MACHINES Filed March 22, 1955 3 Sheets-Sheet 2 Jan. 27, 1959 E osz POWER BRUSHING MACHINES 3 Sheets-Sheet 3 Filed March 22, 1955 TNVEN R K CUM ArmKmEY POWER BRUSHIN G MACHINES Application March 22, 1955, Serial No. 495,951

12 Claims. (Cl. 15-21) This invention relates to power brushing machines of the kind having a power driven rotary wire brush and more particularly relates to machines for brushing gears to remove burrs and the like therefrom.

In the production of gear wheels (such as, for example, spur gears, helical gears and bevel gears) burrs are generally formed on the edges of the teeth at thetwo side faces of the gear. Such burrs occur particularly at the ends of the flanks of the teeth. Heretofore it has been the practice, if power brushing with rotary wire brushes is used for removing these burrs, to employ a brushing machine in which the brush is arranged to brush across the side faces of the gears. Generally the brush is in a fixed position, for example so as to rotate about a horizontal axis, and the gear is slowly rotated beneath the brush with the side faces lying in a horizontal plane. With such an arrangement, however, it is found that the burrs tend to be forced over into the region between the gear teeth and may not be completely removed by brushing. Burrs between the gear teeth are particularly undesirable and for this reason power brushing has not always been a satisfactory method of removing burrs from gear wheels. It is an object of the present invention to provide an improved construction of machine which overcomes these drawbacks.

According to this invention a power brushing machine for brushing a gear comprises a rotary power driven wire brush, a holder for the gear to be brushed, means for rotating the holder in angular steps corresponding to the angular spacing of the gear teeth and means for moving the holder towards and away from the brush in synchronism with the stepwise rotation, the brush and holder being so arranged and positioned that the brush enters successively between pairs of adjacent teeth to brush these teeth along their flanks towards a side face thereof. Conveniently the means for moving the holder towards and away from the brush is arranged so that the brush enters in turn between each successive pair of adjacent teeth.

Generally, a gear only requires brushing immediately adjacent the two side faces and thus even a relatively wide gear can be brushed in two stages, the parts adjacent one side face first being brushed and the gear then being turned over to brush the parts adjacent the other side face.

To facilitate the entry of the brush between the teeth of a gear, the brush is preferably mounted for rotation about an axis at right angles to the axis of the holder.

The brush may be mounted so as to be movable towards or away from the holder.

The following is a description of one embodiment of the invention reference being made to the accompanying drawings in which:

Figure 1 is a view in side elevation of a power brushing machine with part of the outer casing cutaway and the internal structure shown in section and with part of the brush drive mechanism removed;

Figure 2 is a plan view of the machine with the top cover removed;

United States Patent 2,870,467 Patented Jan. 27, 1959 Figure 3 is a vertical section throughthe central column of the machine to show the internal structure; and

Figure 4 is a vertical section through one of the brushdrive mechanisms of the machine.

The machine shown in the drawings is a power-brushing machine for removing burrs and the like from spur gears and comprises a base portion 10 which carries a main central column 11 in which is mounted a holder 12 for the gear to be brushed. Around this holder are arranged four rotary brushes 13 (Figure 2) which are separately driven by electric motors 14 (Figure 1). For clarity in Figure l, the front brush and its mounting and driving mechanism have been omitted from the drawing and the back brush is only indicated diagrammatically. Furthermore, in Figure 1, part of the central column is shown in section along the line 1-1 of Figure 2. The upper part of the central column 11 is shown in section in Figure 3, this section being along the line 3-3 of Figure 2.

The lower part of the central column 11 contains a shaft 16 which is axially slidable in a bearing 17 and is provided with a key-way 18 for preventing rotational movement. The upper end of this shaft 16 is secured to a member 19 which is slidable in a sleeve 20 which extends upwardly beyond the top end of the column 11.

The sleeve 20 is secured at its lower end to a bush 21 which is keyed at 22 to an externally toothed annular gear 23. This gear 23 meshes with a pinion 24 on a shaft 25, which shaft is driven through a reductiongear by an electric motor (not shown) in the base 10 of the machine. The sleeve 20 is rotatable in the column 11, bearings 26, 27 being provided at the upper and lower ends respectively. On the upper end of the sleeve 20, there is secured an annular member 28 carrying a plate 29 secured to the member 28 by

pins

30, 31. The plate 29 has a bush 32 so as to be rotatable on a sleeve 33 which fits around a hollow shaft 34 and is keyed thereto by means of a key 35 slidable in a slot 36 on the shaft. The shaft 34 and the sleeve 33 are eccentric with respect to the sleeve 20. On the sleeve 33 there is carried an externally toothed gear 37, the axis of which coincides with the axis of the sleeve 33 and shaft 34.

Welded to the column 11 is a top member 38 on which is mounted a gear ring 39 having internal teeth, the gear ring axis approximately coinciding with the axis of the column 11. The gear 37 and the gear ring 39 are so dimensioned that the gear teeth are clear of one another except, at any one instant, in one region where they mesh. The gear ring 39 and the gear 37 thus form sun and planet wheels of an epicyclic gear train. Since the gear ring 39 is fixed, as the gear 37 is driven, its axis will move in a circular path around the axis of the gear ring 39. Since the gear 37 is freely rotatable in the bearing 32 which is moved in a circle around the axis of the gear ring 39, the point of contact betweenthe two gears can be moved around their periphery. Rotation of the shaft 25 and hence of the sleeve 20 thus drives the inner gear 37 so that its point of contact with the outer gear ring39 gradually moves around the outer gear. The gear 37 has a number of teeth equal to that of the gear to be brushed whilst the gear ring 39 has one more or one less thanthis number of teeth. Thus as the gear 37 makes one traverse around the periphery of the gear ring 39, it is advanced or retarded about its own axis by one tooth.

The hollow shaft 34 at its lower end is rotatably supported in a bearing 40 on the aforementioned member 19, the bearing being eccentric of the axis of the column 11. It will be noted, however, that the member 19 is secured to the top end of the shaft 16 which in turn, is keyed to the bush 21 so that the bearing 40 for the shaft 34 is rotated with the sleeve 20. Slidably mounted inside the shaft 34 is another shaft 41 the two shafts being connected by driving pins 42, 43 so that the shafts rotate slidable in a slot 44 in the shaft 34. Similarly, the pin 43 is secured in the shaft 34 but is slidable in a slot 45 in the shaft 41. Thus the two shafts are free for relative axial movement. On the shaft 34 there is mounted a holder 46 for the gear to be brushed, this gear being indicated by the dotted lines 47. The gear 47 is retained in the holder 46 by means of radially extending plungers 148 retained by a spring clip 43 which lies in the circumferential groove 49 around the holder. The plungers 148 are pressed outwardly, against the inner surface of the bore in the gear 47, by upward movement of the tapered end of the shaft 41.

The shaft 41 as mentioned above is pinned to the outer shaft 34 to ensure that they rotate together but so as to permit of axial movement within the limits of the slots 44, 45. The pin 43 extends into an annular member 59 carried on the shaft 34. This annular member 56 carries a helical spring 51 which presses upwardly against a second annular member 52 in which are secured the outer ends of the pin 42. Thus the spring 51 serves to urge the inner shaft 41 upwardly with respect to the outer shaft 34 and so retains the gear to be brushed in the holder 46.

As previously mentioned, there are four brushes 33 each driven by a separate electric motor 14. The drive for one of these brushes is shown in more detail in Figure 4. The electric motor 14, through a coupling 64), drives a shaft 61 which is connected by a second coupling 62 to the spindle 63 of a bevel gear 64. The gear 64 meshes with a second bevel gear 65 formed integrally on a hollow shaft 66, which shaft is carried by bearings 67, 68 in the top part 6h of the casing. At one end 76, the hollow shaft 66 is internally splined to engage with mating grooves on a spindle 71 which is slidable in the shaft 66. This spindle 71, at its outer end, is secured to a bush member 72 which is rotatable in bearings 73, 74 carried in a non-rotatable hollow shaft 75', this latter shaft, however, being axially slidable in the casing 69. The shaft 75 may be locked in any desired axial position by means of a screw 76. The brush 13 (not shown in Figure 4) is mounted on the end 77 of the spindle 71. This brush may thus be driven by the electric motor through the

gears

64, 65 and the spindle 71 although the axial position of the spindle and brush is adjustable. The part 69 of the casing and the motor 14 are secured to a column 86 which surrounds the

shafts

61, 63. This column 86, as shown in Figure l, is carried in a mounting 81 forming part of the main structure of the machine, the four mountings 81 for the four brush mechanisms being carried on a support 82 on the central column 11. The columns 80 are adjustable longitudinally in their mountings and also angularly, clamping bolts (not shown) being provided for securing them in the required positions.

The shaft 16 is carried on a hydraulic piston in the base of the machine to permit of the holder 46 for the gear to be brushed to be adjusted in position axially.

It will be seen that the machine described serves to carry the gear 47 towards and away from each brush 13 in turn. Each cyclic movement brings the gear around a step of one tooth so that the brushes 13 brush between each successive pair of teeth. The brushes 13 can be adjusted in position axially and also swung about the axis of the column 80 so as to permit the brushing of gears of various sizes. After a gear has been brushed, it is released from the holder 46 by moving the shaft 16 upwardly a sufficient distance that, after the collar 25 has come into contact with the plate 29, the shaft 41 is moved outwardly relatively to the shaft 34 against spring 51, thereby releasing plungers 143.

I claim:

l. A power brushing machine for brushing a gear comprising a rotary power-driven wire brush, a holder for the gear to be brushed, means for rotating the holder in angular steps corresponding to the angular spacing of the gear teeth and means for moving said holder towards and away from the brush in synchronism with the stepwise rotation so that the brush enters successively between pairs of adjacent teeth to brush these teeth along their flanks towards a side face thereof.

2. A power brushing machine for brushing a gear comprising a main frame, a rotary power-driven wire brush mounted on said main frame, a holder for the gear to be brushed, and an epicyclic gear train including a sun which is fixed on said main frame and a planet which carries said holder for rotating the holder and for moving it towards and away from the brush in synchronism with the rotation so that the brush enters successively between pairs of adjacent teeth to brush these teeth along their flanks towards a side face thereof. i

3. A power brushing machine for brushing a gear comprising a main frame, a rotary power-driven wire brush mounted on said main frame, a mounting rotatably carried in said main frame, a holder for the gear to be brushed eccentrically but rotatably carried in said mounting and means for rotating said mounting in said frame and said holder in said mounting whereby the holder is moved towards and away from the brush and rotated rel ative thereto.

4. A power brushing machine as claimed in claim 3 wherein said means for rotating said holder in said mount ing comprises an epicyclic gear system having a sun wheel fixed on said main frame and a planet wheel secured to said holder, the number of teeth on the planet wheel dilering from that on the holder.

5. A power brushing machine as claimed in claim 4 wherein the number of teeth on the planet wheel is equal to the number of teeth on the gear to be brushed.

6. A power brushing machine as claimed in claim 5 wherein the number of teeth on the planet wheel differs by one from the number of teeth on the sun wheel.

7. A power brushing machine for brushing a gear comprising a main frame, a rotary power-driven wire brush mounted on said main frame, a mounting rotatably carried in said main frame, a holder for the gear to be brushed which holder is secured to an externally toothed gear rotatably carried in said mounting with the axis of the externally toothed gear coinciding with the axis of rotation of the holder in said mounting but eccentric with respect to the axis of rotation of said mounting, an internally toothed gear ring fixed on said main frame to engage said externally toothed gear, the number of teeth on said externally toothed gear differing from that of said internally toothed gear ring and driving means for rotating said mounting in said main frame.

8. A power brushing machine for brushing a gear comprising a main frame, a mounting rotatably carried in said main frame, a rotary power driven wire brush adjustably carried on said main frame for adjustable positioning in a plane at right angles to the axis of said mounting, a holder eccentrically but rotatably carried in said mounting and means for rotating said mounting in said frame and said holder in said mounting whereby the holder is moved towards and away from the brush and rotated relative thereto.

9. A power brushing machine for brushing a gear comprising a main frame, a mounting rotatably carried in said main frame, a rotary power-driven wire brush adjustably carried on said main frame for adjustable positioning in a plane at right angles to the axis of said mounting, a holder for the gear to be brushed which holder is secured to an externally toothed gear rotatably carried in said mounting withthe axis of the externally toothed gear coinciding with the axis of rotation of the holder in said mounting but eccentric with respect to the axis of rotation of said mounting, an internally toothed gear ring fixed on said main frame to engage said externally toothed gear, the number of teeth on said externally toothed gear differing from that of said internally toothed gear ring and driving meansfor rotating said mounting in said main frame.

10. A power brushing machine for brushing a gear comprising a main frame, a mounting rotatably carried in said main frame, a plurality of rotary power-driven wire brushes mounted on said main frame in positions spaced angularly around the axis of rotation of said mounting, a holder for the gear to be brushed eccentrically but rotatably carried in said mounting and means for rotating said mounting in said frame and said holder in said mounting whereby the holder is moved towards and away from the brushes in turn and is rotated relative thereto.

11. A power brushing machine for brushing a gear comprising a main frame, a mounting rotatably carried in said main frame, a plurality of rotary power-driven wire brushes mounted on said main frame in positions spaced angularly around the axis of rotation of said mounting, a holder for the gear to be brushed which holder is secured to an externally toothed gear rotatably carried in said mounting with the axis of the externally toothed gear coinciding with the axis of rotation of the holder in said mounting but eccentric with respect to the axis of rotation of said mounting, an internally toothed gear ring fixed on said main frame to engage said externally toothed gear, the number of teeth on said externally toothed gear difiering from that of said internally toothed gear ring, and driving means for rotating said mounting in said main frame.

12. A power brushing machine for brushing gear comprising a main frame, a rotary power-drive wire brush mounted on said main frame, a mounting rotatably carried in said main frame, a holder for the gear to be brushed eccentrically but rotatably carried in said mounting, said holder being adjustable axially in said mounting, and means for rotating said mounting in said frame and said holder in said mounting whereby the holder is moved towards and away from the brush and rotated relative thereto.

References Cited in the file of this patent UNITED STATES PATENTS 940,988 Quimby Nov. 23, 1909 1,891,331 Lord Dec. 20, 1932 2,579,337 Reaser et al. Dec. 18, 1951 2,722,028 Lynch et a1 Nov. 1, 1955