US2272161A

US2272161A - Differential mechanism

Info

Publication number: US2272161A
Application number: US327309A
Authority: US
Inventors: Frederickson Clayton Erasmus
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-04-01
Filing date: 1940-04-01
Publication date: 1942-02-03
Anticipated expiration: 1959-02-03

Description

Feb 1942. C. E. FREDERICKSQN 2,272,161

DIFFERENTIAL MECHANISM I Filed April 1, 1940 altar/M41513 29 I i 2 gmwrw j I C lay 0112 fie defz c/fson Patented Feb. '3, 1942 I Clayton Erasmus Frcderlckson, Chicago, Ill. Application April 1, 1940, Serial No. 327,309

11 Claims.

My present invention is an improved differential of the type disclosed in my Patent No. 2,203,683, issued June 11, 1950, and the present .pressure angle of the worms H and worm gears I approximately and the helix cut approxi invention, in its specific aspects, has for an ob.- I

ject to provide improved means for mounting the key-worms in the case.

Another object is to reduce the cost of manufacture and increase the life of the key-worms and their bearings.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will be first fully described in the following detailed descrip tion, and then be particularly pointed out in the appended claims, reference being had to the accompanying drawing, in which;

Fig. 1 is a view of one-half the case and its contents, viewed from the plane of separation of the casehalves, the spider and worm pinions being removed.

Fig, 2 is a section On the line 2--2 of Fig. 1.

Fig. 3 is a detail viewof one key-worm and its bearings, which constitute the specific subject I matter of this application.

In the drawing, the parts which bear the same reference number as like parts in my aforesaid patent are the same.

.The present construction illustrated differs from that of my application above referred to in that three key-worm sets are shown instead of four, and the means to mount the key-worms in the case are different. Any number of keyworm sets, however, may be used as desired, depending upon the resistance required-to operate the vehicle with load.

In the present case each key-worm l l is journaled on a pin or stub shaft 21 which has (preferably) reduced

ends

28, 28 tightly pressed or fitted in the holes 33 of the rectangular bearing blocks 29. The blocks 29 have flanges 3| to fit grooves 32 in the recesses 39 of the case. The blocks 29 occupy the full depth of the recesses so that when the case halves are assembled and secured by the cross bolts 4 the blocks 29 in one side mately 19 35 good results can be obtained in that gear noise and shock are reduced to a minimum. The above amounts may, however, vary from 5 to 10 either way and yet operate successfully,

From the foregoing description, taken in connection with the accompanying drawing, it is thought that the construction and advantages of the invention will be clear to those skilled in the art.

What I claim is:

1. In a worm-differential, a case composed of two sections bolted together, each section having chambers provided with hearing block receiving recesses entering from the plane between the sections, key-worms, shafts on which said keyworms rotate, elongated bearing blocks in which the ends of said shafts are secured and between which said key-worms are positioned, a worm, two bearing blocks and. a shaft constituting a unit assembly, said case sections recesses being shaped to receive and fit said bearing blocks, and

worm pinions in said chambers to mesh with said key-worms.

2. In a. worm-differential, a case composed of 'two' sections bolted together, each section having chambers providedwith bearing blo'ck receiving recesses entering from the plane between the sections, key-worms, shafts on which said keyworms rotate, elongated bearing blocks in'which the ends of said shafts-are secured and between which said key-worms are positioned, said case sections recesses being shaped to receive and fit said bearing blocks, and worm pinions in said charnbersto mesh with said key-worms.

3. In a differential mechanism, a two part case,

each part of which has chambers for receiving driving and differentiating worm gears and pinions and connecting key-worms, means to mount the key worms in the case parts, said means comprising bearing block receiving recesses entering from the parting plane of the case parts and extending inwardly therefrom, elongated bearingiblocks in said recesses, those of one case part abutting those of the opposite will abut those in the other side and hence the blocks 29 will be tightly secured in the case and thus maintain the axes of the key-worms always the same distance from the axes of the worm pinions 20, which are mounted on the stub shafts l8 of the spider.

In the practical construction of my worm differential I have found that bymaking the normal case part, shafts carried by each pair of blocks, and key-worms rotatable on said shafts between the blocks of a pair.

- 4. In a differential mechanism, a two part case, each part of which has chambers for receiving driving and diiferentiating orm gears and pinions and connecting key worms, means to mount the key-worms in the case parts, said means comprising bearing block receiving recesses en- I tering from the parting plane of the case parts each part of which has chambers for receiving driving and difierentiating worm gears and pinions and connecting key worms, means to mount the key-worms in the case parts, said means comprising bearing block receiving recesses entering from the parting plane of the case parts and extending inwardly therefrom, elongated bearing blocks in said recesses, shafts carried by each pair of blocks, and key-worms rotatable on said shafts between the blocks of a pair, said case having flanges to fit said grooves.

6. In a diiferential mechanism, a two part case, each part of which has chambers for receiving driving and differentiating worm gears and pinions and connecting key worms, and means to mount the key-worms in the case parts, said keyworms and pinions being constructed so that their normal pressure angle is approximately 25 and their helix cut is approximately 19 35.

7. In a differential mechanism of the character described, a case, key-worms, worm pinions meshing with said key worms, and worm gears meshing with said key worms, said key-worms and worm pinions being constructed so that their normal pressure angle is approximately 25.

8. In a difierential mechanism of the charac ter described, a case having a chamber for receiving driving and difierentiating worm gears and pinions and connecting key worms, means to mount the key worms for rotation within the case chamber comprising bearing block receiving recesses communicating with and extending from the case chamber, bearing blocks in said recesses, a shaft carried by each pair of blocks, and a key worm rotatably supported on each shaft between the blocks of a pair.

9. In a worm-differential, a case having a chamber for receiving co-axial worm gears and, meshing therewith, key worm assemblies each comprising a pair of bearings, a shaft extended between and connecting the two bearings, and a key worm rotatably supported on the shaft, and means extending away from the chamber in a direction parallel with the axes of the worm gears afiording a mounting wherein the bearings may be slidably received and immovably retained.

10. In a differential mechanism, a case having chambers for receiving driving and differentiating worm gears and pinions and connecting keyworms, means to mount the key-worms in the case parts, said means comprising bearing block receiving recesses entering from the parting plane of the case parts and extending inwardly therefrom, elongated bearing blocks in said recesses, those of one case part abutting those of the opposite case part, shafts carried by each pair of blocks, and key-worms rotatable on said shafts between the blocks of a pair, said keyworms and worm pinions being constructed so that their normal pressure angle is approximately 25.

11. In a differential mechanism, a case having chambers for receiving driving and differentiating worm gears and pinions and connecting keyworms, means to mount the key-worms in the case parts, said means comprising bearing block receiving recesses entering from the parting plane of the case parts and extending inwardly therefrom, elongated bearing blocks in said recesses, those of one case part abutting those of the opposite case part, shafts carried by each pair of blocks, and key-worms rotatable on said shafts between the blocks of a pair, said keyworms and worm pinions being constructed so that their normal pressure angle is approximately 25 and their helix cut is approximately 19 35'.

CLAYTON ERASMUS FREDERICKSON.