US2759368A

US2759368A - Gearing

Info

Publication number: US2759368A
Application number: US197721A
Authority: US
Inventors: William H Kitto
Original assignee: G M LAB Inc
Current assignee: G M LAB Inc; G-M LABORATORIES Inc
Priority date: 1950-11-27
Filing date: 1950-11-27
Publication date: 1956-08-21
Anticipated expiration: 1973-08-21

Description

Aug. 21, 1956 w. H. mm 2,759,368

GEARING Filed Nov. 27, 1950 3 Sheets-Sheet l IN VEN TOR W. H. KlTTO GEARING Aug. 21, 1956 3 Sheets-Sheet 2 Filed NOV. 27, 1950 WWW g QM W l mhm 7 QM mE QM WMM United States Patent 0 GEARING William H. Kitto, Evanston, Ill., assignor to G-M Laboratories, Inc., Chicago, 11]., a corporation of Illinois Application November 27, 1950, Serial No. 197,721

6 Claims. (Cl. 74-446) This invention relates to gearing which is particularly adaptable for use in an improved floor polishing and scrubbing machine having a single rotary flat brush which normally supports the weight of the machine.

The principal object of this invention is to provide an improved gearing construction for driving the rotary brush from the machine motor, wherein the gearing has long life under normal operating conditions, wherein gear noise is substantially eliminated, wherein porous bearings and plastic gears are utilized to eliminate the necessity for gear boxes, gaskets, seals and the like, and wherein the gearing may be accurately and inexpensively fabricated.

The improved floor polishing and scrubbing machine utilizing the gearing of this invention is fully illustrated and described in a co-pending application Serial #197,725, filed on November 27, 1950, by Archie J. McMaster, William H. Kitto, and Kurt Burian. The machine includes a base member which is preferably of an inverted cup shaped configuration. A substantially constant speed single phase induction motor is mounted on the upper side of the base member with the motor shaft extending downwardly through the base member. A phasing reactor is also mounted on the upper side of the base member. A cover is secured to the upper side of the base member and encloses the motor and phasing reactor. The lower end of the motor shaft operates a motor pinion meshing with a novel cluster gear carried by a bracket secured to the lower side of the base member. The cluster gear also meshes with a novel output gear carried by a bracket also secured to the lower side of the base member. Mounting means detachably secure a flat rotary brush to the output gear to be driven thereby. A centrifugal clutch is located between the motor shaft and the motor pinion.

All of the component parts of the machine are carried by the single base member so that they may all be accurately positioned with respect to each other with a minimum of efiort, thereby greatly reducing manufacturing and assembly costs. Further, when the brush and cover are removed, the various parts are exposed for ready inspection, cleaning and repair, if necessary.

In assembling the gearing, the cluster gear is brought into proper meshing relation with the motor pinion and then its supporting bracket is securely fastened in place on the base member. Then the output gear is brought into proper meshing relation with the cluster gear and its supporting bracket is tightly secured to the base member. In this way correct meshing of the gearing is assured and the maintenance of close tolerances in the parts is not required. This further decreases the costs of manufacture of the machine.

The engaging teeth of the motor pinion and cluster gear are helically formed to provide a downward thrust on the motor shaft and an upward thrust on the cluster gear during operation for the purpose of eliminating intermittent thrust motion of the motor shaft and cluster gear and noise which would result therefrom. Suitable thrust bearings are provided for the motor pinion and "ice cluster gear. The engaging teeth of the cluster gear and output gear are regularly formed and since the output gear, which carries the brush, supports the weight of the machine, it is also provided with a thrust bearing.

The gears are all rotatably journaled by means of porous bearings supplied with suitable lubricant and the gears are formed of suitable plastic, such as nylon, for oilless and noiseless operation. As a result the necessity for gear boxes, seals, gaskets and the like is eliminated. The gears are unique in construction in that they include metal body portions, plastic tires having the gear teeth formed therein and novel means for securing the plastic tires to the body portions. The tires in blank form are secured to the body portions and then the gear teeth are hobbed in the plastic tires. This provides fast cutting of accurate gear teeth and eliminates the necessity of maintaining close tolerances in the parts.

The output gear is provided with an annular boss and with pins having conical heads for securing the brush to the output gear. The brush is drawn against the annular boss of the output gear and since the brush forms the sole support for the machine, the drawing of the brush against the annular boss of the output gear squares up the machine and prevents wobbling of the machine.

Further objects of this invention reside in the details of construction of the gearing, the cooperative relationship between the component parts thereof and the features of the gearing which particularly adopt the gearing for use in the improved floor polishing and scrubbing machine.

Other objects and advantages of this invention will become apparent to those skilled in the art upon reference to the accompanying specification, claims and drawings, in which:

Fig. 1 is a bottom plan view of a floor polishing or scrubbing machine with the brush removed and utilizing the novel gearing of this invention;

Fig. 2 is an enlarged vertical sectional view taken through line 2-2 in Fig. 1 and showing the brush assembled;

Fig. 3 is an enlarged sectional view of the cluster gear:

Fig. 4 is a sectional view taken along the line 4-4 of Fig. 3;

Fig. 5 is an exploded perspective view of the cluster gear;

Fig. 6 is a vertical sectional view through the output gear;

Fig. 7 is an exploded perspective view of the parts forming the output gear; and

Fig. 8 is a partial bottom view of the output gear.

Referring first to Figs. 1 and 2, the floor polishing and scrubbing machine utilizing the gearing of this invention is generally designated at 10 and includes an inverted cup-shaped base member formed from sheet steel having a side wall 11 and a top wall 12. The top wall 12 is recessed at 13 and is formed with a central bearing seat 14 having a spherical bearing supporting surface 15.

Mounted on the upper side of the base member is an electric motor, which motor may be of the type described in the above mentioned co-pending application Serial #197,725. The lower end of the motor shaft 22 carries within the base member 11, a centrifugal clutch and motor pinion assembly, which is fully shown and described in said co-pending application.

The motor pinion 153 meshes with a large diameter gear 192 of a cluster gear also having a gear of smaller diameter 193. This cluster gear is rotatably carried on a shaft 194 which in turn is secured to a cluster gear bracket 195, the bracket being adjustably secured to the lower side of the upper wall 12 ,of the base member.

The cluster gear is illustrated in more detail in Figs.

3 to 5 and includes a body portion 197 which may be formed of die cast zinc. The upper surface of the body portion 197 is provided with an annular boss 198 and also with a plurality of circumferentially spaced circular bosses 199. 'The gear 192 is formed on a tire made of suitable plastic material such as nylon, the tire being provided with a central opening 200 and a plurality of holes 201. The tire is placed on the upper surface of the body portion 197 with the central opening 200 engaging the annular boss 198 and with the holes 201 receiving the bosses 199. In this way a driving relationship is established between the tire and the body portion. A plate 203 having a central opening and holes 304 is provided for clamping the tire in place on the body portion. In this respect rivets 205 extend through the holes 204 and through hole-s in the bosses 199. The inner part of the-plate 203 rests on an annular shoulder 292 formed on the upper side of the body portion 197.

The body portion 197 has an extension or shank of reduced diameter upon which is mounted the gear 193, the gear being made of suitable plastic such as nylon. The body portion 197 is provided with a plurality of projections 297 extending between the gear teeth on the gear 193. These projections 207 provide a driving connection between the body portion '197 and the gear 193. The gear 193 is provided with an internal recess 208 for receiving a washer 209 which in turn is held in place by peening over at 210 the lower extremity of the body portion 197. In this way the gear 193 is locked in place on the body portion 197.

A sintered porous bronze bearing 213 is secured within the body portion 197 and it seats against an internal shoulder 212. An absorbent washer 214 rests against the upper surface of the porous bearing 213 and the absorbent washer is held in place by a metal washer 215, the metal washer in turn being staked in place as illustrated at 216. The absorbent washer is impregnated with a suitable lubricant for supplying lubricant to the porous bearing 213 for lubricating the running fit between the porous bearing and the cluster gear shaft 194. The washer 215 in addition to encasing the absorbent washer 214 also acts as a thrust washer for the cluster gear.

In forming the cluster gear the smaller diameter plastic gear 193 has its teeth molded or otherwise formed thereon before the gear is applied to the body portion. However, in the case of the larger diameter gear 192, the plastic tire in blank form is first secured to the body portion and then the gear teeth are suitably hobbed or cut after assembly about a center corresponding to the axis of the porous bearing. This assures an accurate relation between the central axis of the cluster gear and the teeth of the larger gear 192. The gear teeth may thus be accurately and rapidly formed with small expense in this manner.

The cluster gear is rotatably mounted on the shaft 194 which in turn is provided at its upper end with a shoulder engaging the bracket 195, the shaft being held in place on the bracket 195 by peening over the upper end thereof as at 218. A resilient thrust washer 220 preferably made of impregnated cork is located between the bracket 195 and the washer 215. There is thus provided a resilient thrust bearing for the cluster gear. The bracket 195 is adjustably secured to the base member by screws 219. v

Preferably the gear teeth of the motor pinion 153 and the gear teeth of the gear 192 of the cluster gear are helically formed for the purpose of maintaining substantially constant thrust on the motor shaft and on the cluster gear. The direction of the helices is such that upon operation of the machine a downward thrust is provided on the motor shaft and an upward thrust on the cluster gear. This upward thrust is absorbed by the resilient upper thrust bearing of the cluster gear.

The smaller gear 193 of the cluster gear meshes with an output gear 225 which is rotatably mounted on a'shaft 226, the shaft being carried by a bracket 227 adjustably secured to the lower side of the upper wall 12 of the base member.

The output gear 225 is illustrated in more detail in Figs. 6 to 8. The output gear includes a tire formed of suitable plastic material such as nylon in which the gear teeth are formed. It also includes a body portion 229 for carrying the tire. The body portion 229 may be formed of die cast zinc and is provided with an external shoulder 230 received in a groove formed in the lower side of the tire. The tire is provided with an internal surface 232 engaging the exterior of the body portion 229 and the body portion is provided with a plurality of lugs 231 received in notches 233 in the tire. In this way a driving connection is provided between the tire and the body portion. The top of the body portion 229 is provided with a plurality of circular bosses 234 which are received in holes 235 in a clamping disc 236. The outer edge of the clamping disc 236 is provided with a downwardly extending flange 237 received in a suitable groove in the tire. The disc 236 is fastened to the body portion 229 by peening over the bosses 234 as indicated at 238 and also securely clamps the tire in place on the body portion. The upper surface of the body portion is provided with an annular groove 240 in which is received an absorbent washer 241 impregnated with suitable lubricant. The disc 236 partially overlies the absorbent washer for retaining the same in the annular groove. A sintered porous bronze bearing 242 is carried by the body portion 229 and it is provided with an annular flange 243 which also partially overlies the absorbent washer 241. The absorbent washer 241 supplies lubricant to the porous bearing 242 for lubricating the running fit between the bearing and the shaft 226. The flange 243 on 'the upper end of the bearing 242 also serves as a thrust surface for the output gear and the thrust surface must be normal to the axis of rotation of the output gear. To obtain the desired accuracy a shouldered punch is pressed into the bore of the bearing 213 with an interference fit until the shoulder strikes the fiange for sizing the bore and squaring the flange. Then the bearing and punch are pressed into place with an interference fit for accurately locating the bearing in the body portion. Then the punch is removed from the bearing.

The body portion 229 is provided with a pair of holes 245 and likewise the disc 236 is provided with a pair of holes 246, these holes receiving a pair of downwardly projecting pins 247 which are riveted in place as indicated at 248. 'These downwardly extending pins 247 are provided with enlarged heads having a conical surface 249 and a bead 250. These pins provide means for removably securing a brush to the output gear and also provide additional means for fastening the disc 236 to the body portion 229 for clamping the tire in place.

The bracket 227 is illustrated in Figs. 1 and 2. It includes a plurality of legs 252 terminating in attaching ears 253 having slots 254. The bracket is secured to the base member by screws 255 and nuts 256, the screws 255 passing through the slots 254 and suitable holes in the base member. The lower surface of the bracket 227 has a plate 257 secured or Welded thereto as indicated at 258. The shaft 226 is provided with a shoulder resting against the plate 257 and is held in place on the bracket by peening over the upper end of the shaft as indicated at 260. A thrust Washer assembly is interposed between the disc 257 and the output gear bearing flange 243. This thrust bearing assembly includes a metal cup-shaped member 262 having a running engagement with the porous bearing flange 243 and a resilient washer 261 carried within the cup-shaped member 262. The resilient washer forms a resilient thrust bearing for the output gear. The lower end of the shaft 226 is provided with an annular groove 263 for receiving a split washer 264 for holding the output gear in place on the shaft 226. The lower side of the output gear is provided with a "cover 265 forenclosing the output gear bearing 242 and the shaft 226 to prevent dirt and foreign material from going into the bearing.

The plate 257 overlies the disc 236 and is spaced a slight distance therefrom. The plate 257 acts as a stop for the output gear to prevent undue tilting of the output gear with respect to the machine. The spacing between the plate 257 and the output gear disc 236 is such that the parts are not strained or stressed beyond their elastic limits when and if tilting should occur.

The output gear bracket 227 is provided with an extension 267 terminating in an ear 269 provided with a hole 270. An opening 268 is also provided in the extension 267. The extension 267 and ear 269 form an outboard support for the cluster gear shaft 194. In this respect a thrust Washer 271 of fiber or other suitable material is interposed between the cluster gear and the ear 269. I screw 272 is received in the lower end of the cluster gear shaft 194 for anchoring the same to ear 269 of the bracket 227. The opening 268 in the extension 267 is for accommodating the

gears

193 and 225 so that these gears may mesh through that opening.

The gear teeth of the

gears

193 and 225 are conventional in form and preferably the gear teeth of the gear 225 are also cut or hubbed in the plastic tire after the tire has been secured in place on the body portion 229. This provides for accurate and ineXpensiVe formation of the gear.

In assembling the gearing enclosed within the inverted cup-shaped base member 11, the gear 192 is first brought into proper meshing relation with the motor pinion 153 and then the supporting bracket 195 is securely fastened in place on the base member. Then the output gear 225 is brought into proper meshing relation with the cluster gear 193 and the supporting bracket 227 is then tightly secured to the base member. In this way correct meshing of the gearing is assured and the maintenance of close tolerance in the parts is not required.

The output gear detachably carries a rotatable brush. This brush includes a brush backing 285 carrying a plurality of rows of brush bristles 286. The brush backing 285 of annular form is secured to a sheet metal disc 2 57 by means of rivets 288. The disc 287 has an annular surface 289 for engaging an annular shoulder 29%) on the output gear. The disc is connected with the output gear by means of pins 247 in the manner fully described in the above mentioned co-pending application Serial #197,725.

From the above description, it is seen that the present invention has provided a novel gearing fully capable of accomplishing the objects heretofore set forth. More specifically, it is seen the the present invention has provided a novel gearing which is of relatively simple construction and may be inexpensively manufactured and assembled. Furthermore, it is seen that the gearing of the present invention eliminates the necessity for gear boxes, gaskets, seals and the like. In addition, by reason of the novel construction of the gearing of this invention, increased operating life is obtained, and gear noises are substantially eliminated.

While for the purposes of illustration one form of this invention has been disclosed, other forms thereof may become apparent to those skilled in the art upon reference to this disclosure and, therefore, this invention is to be limited only by the scope of the appended claims.

I claim as my invention:

1. A cluster gear comprising a metal body portion having a shank, a central bore and an annular seating surface, a bearing in the central bore for rotatably mounting the cluster gear, an absorbent washer for containing lubricant and contacting the bearing for supplying lubricant to the bearing, a gear carried by the shank of the body portion, interlocking means on the gear and the body portion for establishing a driving connection between the gear and the body portion, means for securing the gear in place on the shank of the body portion, a

tire having gear teeth seating on the annular seating surface of the body portion, interlocking means on the tire and the body portion for establishing a driving connection between the tire and the body portion, and means for securing the tire in place on the body portion.

2. A gear comprising, a gear body having a central bore provided with an internal shoulder, a bearing memher having an external shoulder located in the central bore with the shoulders in engagement, an absorbent washer for containing lubricant located in the central bore and engaging the end of the bearing member for supplying lubricant to the bearing member, and a metal washer secured to the gear body for retaining the absorbent washer in place and for taking end thrust of the gear body.

3. A gear comprising, a gear body having a central bore, an annular groove about the central bore and an annular seating surface, a porous bearing member located in the central bore and having a flange partially overlying the annular groove and forming an end thrust member for the gear body, an absorbent washer for containing lubricant located in the annular groove and engaging the flange for supplying lubricant to the porous bearing member and its flange, a tire have gear teeth and seating on the annular seating surface of the gear body, and an annular disc carried by the gear body for securing the tire in place on the gear body and also partially overlying the annular groove for maintaining the absorbent washer in place therein.

4. A gear comprising, a body portion having a central bore and an annular seating surface, a bearing member in the central bore for rotatably mounting the gear, an absorbent washer for containing lubricant and contacting the bearing for supplying lubricant to the bearing, a tire seating on the annular seating surface and having gear teeth, interlocking means on the tire and body portion for establishing a driving connection between the tire and the body portion, and means for clamping the tire in place on the body portion.

5. A gear comprising, a gear body having a central bore, an annular groove about the central bore and an annular seating surface, a porous bearing member having a bored sleeve portion and a flange at one end, said bearing member being accurately disposed within the central bore of the gear body, with the sleeve portion having an interference fit with the central bore of the gear body and with the flange squared with respect to the bore of the fitted sleeve portion and engaging the gear body and partially overlying the annular groove, said bored sleeve portion of the bearing member forming a rotating bearing for the gear body and said flange forming a thrust bearing for the gear body, an absorbent washer containing lubricant located in the annular groove and engaging the flange for supplying lubricant to the porous bearing member and its flange, a tire having gear teeth and seating on the annular seating surface of the gear body, and an annular disc carried by the gear body for securing the tire in place on the gear body and also partially overlying the annular groove for maintaining the absorbent washer in place therein.

6. A cluster gear, comprising a body portion having a shank, a central bore in said shank, and an annular seating surface, a gear carried by the shank of said body portion, means extending from said body portion between the teeth of said gear for establishing a driving connection between the gear and the body portion, and a tire having gear teeth seating on the annular seating surface of the body portion.

References Cited in the file of this patent UNITED STATES PATENTS 402,448 Hersh et al Apr. 30, 1889 (Other references on following page) 7 UNITED STATES PATENTS Challincr Jan. 26, 1892 Alden et a1. June 26, 1917 Plunkett June 24, 1924 Laddon et a1. Aug. 30, 1927 Frederick Nov. 26, 1929 Adams July 28, 1931 8 Morton Oct. 30, 1934 Church NOV. 26, 1935 Wcnnerstrom Dec. 31, 1935 Hoof Mar. 22, 1938 Colomb Oct. 22, 1940 Etchells June 5, 1945 Clark Jan. 3, 1950