US3667312A

US3667312A - Drive reduction mechanism

Info

Publication number: US3667312A
Application number: US105540A
Authority: US
Inventors: Howard C Dahl
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-01-11
Filing date: 1971-01-11
Publication date: 1972-06-06
Anticipated expiration: 1989-06-06

Abstract

An electric motor is secured to a side wall of a housing formed in part from a short length of stock metal tubing. The drive shaft of the motor is parallel to the axis of the tubing. A belt and pulley drive interconnects the motor shaft with one end of a worm shaft which extends axially through the tubular housing and meshes with a worm gear supported in the housing. The worm gear is secured to an output shaft which projects through a wall of the housing and extends perpendicular to the worm shaft. The worm shaft and the output shaft are supported by bearings contained within bearing housings which are welded to wall or closure portions of the tubular housing.

Description

United States Patent Dahl [ 1 June 6,1972

[54] DRIVE REDUCTION MECHANISM [72] Inventor: Howard C. Dahl, 6420 Nyanza Park Drive, Tacoma, Wash. 98499 [22] Filed: Jan. 11, 1971 21 App]. No.: 105,540

[52] 11.5. C1 ..74/425, 254/170 [51] Int. Cl .Fl6h 1/18, B66d1/00 [58] Field of Search ..74/425; 254/170 [56] References Cited UNlTED STATES PATENTS 2,085,815 7/1937 McCollum ..254/170 2,578,151 12/1951 Ronfeldt ....74/425 2,884,800 5/1959 Carrol ..74/425 Primary ExaminerLeonard H. Gerin Attomey-Graybeal, Cole & Barnard [57] ABSTRACT An electric motor is secured to a side wall of a housing formed in part from a short length of stock metal tubing. The drive shaft of the motor is parallel to the axis of the tubing. A belt and pulley drive interconnects the motor shaft with one end of a worm shaft which extends axially through the tubular housing and meshes with a worm gear supported in the housing.

The worm gear is secured to an output shaft which projects through a wall of the housing and extends perpendicular to the worm shaft. The worm shaft and the output shaft are supported by bearings contained within bearing housings which are welded to wall or closure portions of the tubular housing.

7 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION comprise a housing of cast construction to which a drive 1 motor is secured by a special end mount, with the shafi of the motor projecting into the housing. A reduction gearing train is supported within'the housing and such gearing is interconnected between the motor shaft and an output or load shaft which projects outwardly from a wall portion of the housing. The end mounting of the motor requires a special mounting member, the cast housing requires that patterns be made, and the use of gears exclusively in the reduction train requires the presence of several gears, bearings for each gear, and a support wall or flange for each gear designed into the housing. All of these features contribute to making the mechanism relatively expensive to manufacture. Also, the end mounting of the motor on the housing results in the motor projecting outwardly from the housing an amount equal to its maximu dimension, i.e., its length.

Examples of known prior art reducer drive mechanisms of this type are shown by U.S. Pat. No. 2,67l,880, granted Mar. 9, 1954, to Ralph F. Symonds; by U.S. Pat. No. 2,759,703, granted Aug. 21, 1956, to Tracy S. Holmes; by U.S. Pat. No. 3,l40,856, granted July 14, 1964, to Edward F. Carpenter; and by U.S. Pat. No. 3,467,359, granted Sept. 16, 1969, to Roy L. Durand.

SUMMARY OF THE INVENTION The power drive mechanismv of the present invention is characterized by a reduction gearing housing fabricated from a short length of metal tubing. A bottom wall is welded to one end of the tubular member and a cover is removably. secured to the opposite end. A worm shaft extends axially through the housing and is supported by bearings contained within bearing housings welded to the bottom wall and the cover. A wonn section on the shaft meshes with a worm gear within the housing. The worm gear is pinned or otherwise secured to an intermediate portion of an output shaft. The output shaft is supported for rotation by means of bearings housed within bearing housings which are welded to side wall portions of the tubular housing. A drive motor (e.g., electric) is mounted to a side wall of the housing with its shaft parallel to the worm shaft, whereby the motor adds its smaller (i.e., its width) dimension to the housing, andmay be secured to the housing by use of a conventional side located mounting plate. A belt and pulley drive interconnects the motor shaft with one end of the worm shaft and provides the first stage reduction, with the worm shaft providing a second stage reduction.

According to the invention the housing may be bolted to one end of a mounting base which may in part be fabricated from a length of standard structural channel. A bearing carrying standard is bolted to the opposite end of such base to receive and support the opposite end of the output shaft. A winch drum or the like may be keyed or otherwise secured to the output shaft, to be driven thereby.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a side elevational view of a winch assembly constituting a preferred embodiment of the invention;

FIG. 2 is a sectional view, with some parts fragmented and some parts in top plan, taken substantially along line 2-2 of FIG. 1;

FIG. 3 is a vertical sectional view, with some parts shown in side elevation, taken substantially along line 3-3 of FIG. 1; and

FIG. 4 is an exploded perspective view showing the principal components of the preferred embodiment, but omitting unimportant elements like bearings and fasteners, and also omitting the internal components of the gear reduction housmg.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As best shown by FIGS. 1 and 4, the illustrated embodiment of the invention is a winch unit. It comprises a base member 10, an electric drive motor 12, a gear reduction housing 14, a belt and pulley drive 16, a winch drum l8 and a support standard 20. I

The base member 10 comprises an upper mounting panel 22,

short side walls

24, 26, and bolting

plates

28, 30 welded to the lower edges of the

walls

24, 26 and extending laterally outwardly therefrom, substantially parallel to the mounting panel 22.

Preferably, the gear reduction housing 14 is fabricated from a short length of stock rectangular tubing cut from a long piece of tubing of appropriate dimensions. As a result, its four side walls are of one-piece construction. A bottom wall 32 is slightly inset into the bottom portion of tubular member 14, as shown by FIG. 3, and is welded in place..Bolt receiving strips of metal 34 are welded to the inside of member 14 immediately adjacent the upper end thereof. A top plate 36 is removably secured to the member 14 by a plurality of machine bolts 38 which extend through sized openings in plate 36 and screw into tapped openings formed in the strips 34.

The housing 14 is secured to one end of base member 10, such as by means of nut and bolt assemblies) (FIG. 3) connecting bottom wall 32 to panel 22. The drive motor 12 is secured to the outer side wall 42 of housing 14, such as by means of nut and bolt assemblies 44 (FIG. 2). The bolts are shown to extend through slot apertures 46 provided in a mounting base 48 on the motor 12, and through openings 50 in the side wall 42.

The drive shaft 52 of motor 12 is oriented to be in parallelsim with the axis of housing 14. A relatively small diameter drive pulley 54 is secured to the motor drive shaft 52. Pulley 54 is connectedv to a second larger diameter pulley 56 by means of a V-belt 58. Pulley 58 is secured to the lower end portion of a worm shaft 60. Worm shaft 60 is vertically oriented within end housing 14 and includes a drive worm 62 intennediate its ends. Worm 62 meshes with a worm gear 64.

According to the invention an upper bearing housing 66 of tubular form is welded to the top plate 36 and alower bearing housing 68, also of tubular form, is welded to the bottom plate 32. The bearing

housings

66, 68 are coaxially arranged and each houses appropriate bearings for handling both radial loads and end thrust. Similarly, tubular bearing housings 70, 72 (FIG. 2) are welded to opposed inside wall portions of housing 14 and receive suitable bearings for joumaling an output shaft 76. The driven end of output shaft 76 projects through an opening made in wall 78, through bearing housing member 72 (and the bearing therein) welded to such wall 78 about such opening, then through the hub 80 of worm gear 64, and into bearing housing 70 (and the bearing therein). Hub 80 is pinned or otherwise secured to the output shaft 76.

The opposite end of output shaft 76 may be received within a suitable bearing contained within another bearing housing 82 which is welded or otherwise secured to the upstanding support standard 20. Standard 20 may be fabricated from several pieces of plate material welded together. It is shown to comprise a lower base plate 84 which is secured, such as by bolts 86( FIG. 1), to the end of top panel 22 opposite the housing 14. The winch drum 18 is pinned or otherwise secured to the output shaft 76. v

In this embodiment, a first gear reduction is obtained by the belt and pulley drive (e.g., in the order of 3.5:1 and a second in a quite simple manner and by use of a small number of rela- 54, 56 and precision orientation of the motor and

worm shafts

52, 60, and this simplifies construction.

In the illustrated embodiment the belt and pulley drive 16 is located at the lower end of the motor, and the base member 10 is cut away at 88 to provide clearance for the pulley 56. However, it is to be understood that in other embodiments the motor 12 could be turned end for end and the belt and pulley drive 16 be relocated at the upper end of the housing 14.

The upper end portion 90 of the worm shaft 60 is allowed to project upwardly above the top plate 36. A hand crank or the like may be attached to this upper end portion 90 to provide a manual drive usable in case of motor failure, etc. Also, a brake may be attached to end portion 90 or end portion 90 may be used to drive an accessory. c

It is to be understood that something other than the winch drum 18 may be secured to the output shaft 76 to be driven thereby. Also,.in some installations a relatively narrow winch drum 18 can be used and be supported solely by the bearings within bearing

housing

70, 72, with the support standard 84 and the bearing carried thereby being eliminated.

Since the four sides and the top of gear housing 14 are planar, it is convenient and easily possible to mount control units or other items on such side walls and top plate.

It is to be understood that these and other modifications can be made without departing from the spirit of the invention and the scope of the invention is not to be limited to the illustrated embodiment and the foregoing description, but by the appended claims.

What is claimed is:

l. Reduction drive mechanism comprising:

wall means forming a housing;

a worm shaft in said housing having a worm section intermediate its length;

a motor secured to an outside portion of said housing, and

' including a drive shaft in substantial parallelism with the worm shaft;

belt and pulley means dri'vingly connecting the drive shaft of the motor to an end portion of the worm shafi; output shaft means projecting laterally through said housing generally perpendicularly to the worm shaft; and

a worm gear secured to said output shaft within said housing, said worm gear meshing with the worm section of the worm shaft.

2. Reduction drive mechanism according to claim I, wherein said housing is fabricated from a length of tubing and its wall means includes side wall means of one-piece integral construction, and wherein an opening is provided through a portion of the said side wall means for receiving the output shah means and a bearing-containing bearing housing is secured to said side wall means around said opening, and a portion of the output shaft means extenck through the bearing housing.

3. Reduction drive mechanism according to claim 2, further comprising closure means for the opposite ends of said housing, each said closure means carrying a bearing housing and bearing means within said housing for receiving an end portion of the worm shaft.

4. Reduction drive mechanism according to claim 2, wherein said length of tubing has rectangular proportions and the side wall means comprises four perpendicularly related side walls, said motor includes a side located mounting plate, and said mounting plate is secured to one of the housing side walls.

5. Reduction drive mechanism comprising: a short length of tubing forming one-piece slde wall means for a housing;

a worm shaft in said housing, extending axially thereof, and

including a worm section intermediate its length;

a motor including a drive shaft;

means drivingly connecting the drive shaft of the motor to an end portion of the worm shaft; 7

output shaft means projecting laterally through said housing generally perpendicularly to the worm shaft;

a worm gear secured to said output shaft within said housing, said worm gear meshing with 'the worm section of the worm shaft;

bearing housings secured to opposed side wall portions of said housings and including bearing means for receiving and joumaling the output shaft means for rotation; and

end closures for said housing, including opposed bearing housings including bearing means for receiving and journaling the end portions of said worm shaft.

6. Reduction drive mechanism according to claim 5, wherein said means drivingly connecting the drive shaft of the motor to an end portion of the worm shaft comprises a relatively small pulley on the drive shaft of the motor, a larger pulley secured to the end portion of the worm shaft, and a belt interconnecting the two pulleys, such belt and pulley drive providing a first stage reduction and the worm and worm gear drive providing a second stage reduction.

7. Reduction drive mechanism according to claim 5, further including an elongated base member, means securing one of the end closures of said housing, and hence the housing and its contents, to an end portion of said base member, and means at the opposite end of said base member for receiving and journaling the opposite end of the output shaft.

Claims

1. Reduction drive mechanism comprising: wall means forming a housing; a worm shaft in said housing having a worm section intermediate its length; a motor secured to an outside portion of said housing, and including a drive shaft in substantial parallelism with the worm shaft; belt and pulley means drivingly connecting the drive shaft of the motor to an end portion of the worm shaft; output shaft means projecting laterally through said housing generally perpendicularly to the worm shaft; and a worm gear secured to said output shaft within said housing, said worm gear meshing with the worm section of the worm shaft.

2. Reduction drive mechanism according to claim 1, wherein said housing is fabricated from a length of tubing And its wall means includes side wall means of one-piece integral construction, and wherein an opening is provided through a portion of the said side wall means for receiving the output shaft means and a bearing-containing bearing housing is secured to said side wall means around said opening, and a portion of the output shaft means extends through the bearing housing.

5. Reduction drive mechanism comprising: a short length of tubing forming one-piece side wall means for a housing; a worm shaft in said housing, extending axially thereof, and including a worm section intermediate its length; a motor including a drive shaft; means drivingly connecting the drive shaft of the motor to an end portion of the worm shaft; output shaft means projecting laterally through said housing generally perpendicularly to the worm shaft; a worm gear secured to said output shaft within said housing, said worm gear meshing with the worm section of the worm shaft; bearing housings secured to opposed side wall portions of said housings and including bearing means for receiving and journaling the output shaft means for rotation; and end closures for said housing, including opposed bearing housings including bearing means for receiving and journaling the end portions of said worm shaft.