US2742740A

US2742740A - Rubbing machine

Info

Publication number: US2742740A
Application number: US414785A
Authority: US
Inventors: Douglas E Jones
Original assignee: PENINSULA TOOL Co
Current assignee: PENINSULA TOOL Co
Priority date: 1954-03-08
Filing date: 1954-03-08
Publication date: 1956-04-24
Anticipated expiration: 1973-04-24

Description

April 24, 1956 D. E. JONES RUBBING MACHINE Filed March 8, 1954 IN V EN TOR.

flozgZcw 2.170% BY United States Patent RUBBING MACHINE Douglas E. Jones, Menominee, Mich., assignor to Peninsula Tool Company, Menominee, Mich., a corporation (If-Michigan Application March 8, 1954, Serial No. 414,785

8 Claims. (Cl. 51-170) This inventionrelates torubbing machines and is more particularly concerned withimprovements in small portable devices of this character which have a power driven oscillating shoe adapted to carry a rubbing element for sanding, bufling, polishing or otherwise finishing a surface.

It is a general object of the invention to provide a relatively small, portable, power driven rubbing machine, which is rugged in construction and will withstand hard usage, which is highly efficient in operation, and which may be economically manufactured.

It is a further object of the invention to provide in l a portable rubbing machine of the motor driven oscillating shoe type an improved flexible connection between the shoe and the motor supporting frame which comprises hollow, open ended, upright'tube formations of flexible material arranged in pairs at opposite ends of the shoe, each pair of tube formations being connected to the shoe by a generally 'U-shaped bracket having its leg portions extending upwardly from the shoe between the tube formations and attached to the upright Walls of the latter at tangential points, the tube formations being attached at opposite points on the upright walls thereof to depending portions of the motor supporting frame.

These and other objects and advantages of the invention will be apparent from a consideration of the rubbing machine which is shown by way of illustration in the accompanying drawings, wherein:

Fig. 1 is a side elevation of a power driven rubbing machine embodying the principles of the invention, the lower portion thereof being broken away to show the mechanism in longitudinal section;

Fig. 2 is a section taken generally on the line 2-2 of Fig. l; and

Fig. 3 is a partial perspective of one end of the machine showing the flexible tubular connecting members between the rubbing shoe and the motor housing.

Referring to the drawings there is illustrated a motor driven mechanism which is constructed in accordance with the principles of the invention. The details of the motor are not illustrated and are immaterial to the invention, it being understood that an electric motor, an air motor or any similar type of power means may be employed for providing power in the drive shaft of the machine.

The illustrated machine comprises a frame consisting of a motor housing 10 and a downwardly opening extension thereon which forms a pad or shoe supporting casing section 11. The motor housing 10 and the casing 11 are conveniently formed as a single integral casing, as shown.

The driving motor (not shown) is supported in the housing 10 and provides a downwardly projecting power shaft '13 which extends downwardly into the casing section 11 and is supported in the bearing member 14 which is mounted in the recessed aperture 15 in the cross support 16, the latter being secured to the bottom of the housing 10 and projecting into the casing section 11. A fan 17 is secured on the power shaft 13 above the 'casing 11 and provides for circulation of air through slots (not shown) in the housing 10.

The housing 10 is provided with a laterally or rearwardly extending handle formation 18 which provides a means fortheoperator to grasp the machine in one hand. The handle 18 also accommodates a current supplying cord and a controlling switch (not shown). A knob 19 is mounted on the forward portion of the casing to provide a means for grasping the tool with the other hand and for holding the tool against the work.

A rubbing pad or shoe 20 supports the rubbing element 21 which maybe an abrasive coated sheet, as illustrated, or any other element suitable for engaging the work surface to be treated. The rubbing shoe 2%) comprises .a rigid backing plate member 22 and a pad-like member 23 of rubber, felt or similar resilient material. The pad '23 accommodates on its lower face the abrasive element 21.

The rubbing shoe 20 is connected in spaced relation to the downwardly opening casing 11 by means of flexible connecting

members

24, 25 and 26, 27 which are arranged in paired relation at opposite ends of the casing 11. The

members

24, 25,26 and '27 are identical in construction being characterized by a relatively short length of flexible tubing of rubber or fabric reinforced rubber. The wall thickness is sufiicient to withstand the oscillating or rolling action to which these members are subjected in use. The connecting

members

24 and 25 are arranged in laterally spaced relation at one end of the machine and secured relative to the rigid backing plate 22, by means of "an upright, U-shaped bracket 28 which has its bight portion 29 secured to the upper face of the backing plate 22 by screw fasteners 30. The

members

24 and 25 are arranged with opposed side walls attached to the upwardly extending

legs

31 and 32 of the bracket 28 by means of bolt or screw fasteners 33 and 34, which are provided with suitable elongate clamping Washers 35 and 36, to hold the

members

24 and 25 in proper vertical alignment. At their opposite sides the

members

24 and 25 are attached to the

vertical side walls

37 and 38 of the casing 11 by means of bolt or

screw fasteners

39 and 40 which extend through the oppositely disposed side walls of the members and which are provided with suitable vertically extending elongate nut forming clamp plates 41 and 42. The pair of

members

26 and 27 at the opposite end of the casing 11 are attached to the plate 22 by means of a bracket 28', which is identical with the bracket 28, and to the

casing Walls

37 and 38 in the same manner as

members

24 and 25. All of the connecting

members

24, 25, '26 and 27 are compressed into an oval cross section in their normal position as shown in'Fig. 2 to permit the plate 22 to move relative to the casing 11 in an orbitual path, the movement being limited in accordance with the flexibility of the members.

The lower end of the driven shaft 13 is secured in a recess 43 in the upper face of an eccentric 4 A recess 45 in the lower face of the eccentric 4-4 receives a bearing 46 which is secured on a short post member 47 attached to the center of the backing plate 22 by a screw or bolt fastener 48. The vertical axes of the drive shaft 13 and the post 47 are, of course, offset to give an eccentric motion to the shoe 20 when the eccentric 44 is rotated by operation of the shaft 13. The eccentric 44 is provided with a counterweight arm 49 which reduces the vibration in the device.

The rubbing shoe 20 is preferably provided at its ends with clamping means for securing in position thereon the abrasive coated sheet 21. The illustrated securing means comprises a cross shaft member 50 of square cross section arranged adjacent each end of the plate 22. The cross shaft members 59 are identical and are secured in the same manner to the plate 22. The members 50 are formed at the ends with

cylindrical bearing sections

51, 51 which are held in rotatable relation beneath the curved ends 52, 52' of

spring retainer plates

53, 53 which are secured by screw or

rivet fasteners

54, 54. The ends of the members 50 may be slotted to receive a screw driver or other tool for rotating the same in frictional engagement with the turned over ends of the abrasive sheet 21 to secure the same in clamping relation on the top of the plate.

While specific materials and particular details of construction have been referred to in describing the invention it will be understood that other materials and variations in the details of construction may be resorted to within the spirit of the invention.

I claim:

I. in a rubbing machine having a rubbing shoe, a supporting housing and a power driven shaft extending into said housing, an eccentric connection between the driven shaft and the center portion of the shoe for oscillating the shoe relative to the housing, a plurality of flexible, tubular connecting members between the housing and marginal portions of the shoe, which connecting members are arranged in oppositely disposed relation adjacent the periphery of the housing with the long axis thereof generally parallel to the power driven shaft, and means for securing opposite side wall portions of each of said connecting members to the shoe and to an adjacent portion of said housing.

2. In a rubbing machine having a vibratable shoe, a supporting housing and a power driven shaft extending into said housing, an eccentric connection between the driven shaft and the shoe for vibrating the shoe, a plu rality of flexible, tubular connecting members between the housing and marginal portions of the shoe, which connecting members are arranged in paired relation at opposite sides of the housing adjacent the periphery of the housing and with the long axis thereof generally perpendicular to the plane of the shoe, means for securing side wall portions of each of said connecting members to an adjacent portion of said housing, and bracket means for securing opposed side wall portions of said connecting members to said shoe.

3. In a rubbing machine having an oscillatable shoe, a supporting housing having oppositely disposed side walls and a power driven shaft extending into said housing, an eccentric connection between the driven shaft and the shoe for oscillating the shoe, a plurality of hollow, flexible cylindrical connecting members between the side walls of the housing and marginal portions of the shoe, which connecting members are arranged in opposed and paired relation, means for securing side wall portions of each of said connecting members against adjacent side wall portions of said housing, a bracket member projecting upwardly of said shoe between the connecting members of each pair thereof, and means for securing opposite side wall portions of said connecting members to said bracket.

4. A rubbing machine comprising a housing having side wall members framing an open end, a rubbing shoe positioned over the open end in spaced relation thereto, a power driven shaft extending in said housing and terminating short of said shoe. :1 fixed shaft extending from said shoe into said housing in offset relation to said power driven shaft, a counterweightecl eccentric connecting said shafts whereby said shoe is vibrated upon rotation of said power driven shaft, independent flexible connections between marginal portions of said shoc and the side wall members of said housing adjacent said opening for limiting the vibrational movement of said shoe, said flexible connections comprising peripherally spaced hollow tube-like sections of resilient material arranged with the long axis thereof normal to the surface of the rubbing shoe, fastener members connecting side wall portions of said tube-like sections to the internal surfaces of the side wall members of said housing and angular bracket members connecting opposite side wall portions of said tube-like sections to said shoe.

5. A rubbing machine comprising a housing having side wall members framing an open end, a rubbing shoe having a rigid backing plate positioned over the open end in spaced relation thereto, a power driven shaft extending in said housing and terminating short of said backing plate, a fixed shaft extending from said backing plate into said housing with the long axis thereof in offset relation to the axis of rotation of said power driven shaft, a counterweighted eccentric connecting the ends of said shafts whereby said shoe is vibrated upon rotation of said power driven shaft, independent flexible connections between peripheral portions of said backing plate and the side wall members of said housing adjacent said opening for limiting the vibrating movement of said shoe, said flexible connections comprising peripherally spaced tubular sections of rubber-like resilient material arranged with the long axis thereof normal to the surface of the rubbing shoe, fastener members connecting side wall portions of said tubular sections to the internal surfaces of the side wall members of said housing and angular bracket members connecting opposite side wall portions of said tube-like sections to said shoe, with said tubular sections being normally compressed in the transverse direction.

6. A rubbing machine comprising a housing having side wall members framing an open end, a rubbing shoe positioned over the open end in spaced relation thereto, a power driven shaft extending in said housing and terminating short of said shoe, a fixed shaft extending from said shoe into said housing in olfset relation to said power driven shaft, a counterweighted eccentric connecting said shafts whereby said shoe is vibrated upon rotation of said power driven shaft, independent flexible members spaced outwardly of said eccentric and connecting said shoe with the side wall members of said housing adjacent said opening for limiting the vibrational movement of said shoe, said flexible members comprising peripherally spaced hollow tube sections of rubber-like resilient material arranged with the long axis thereof normal to the surface of the rubbing shoe, fastener members connecting side wall portions of said tube sections to the .internal surfaces of the side wall members of said housing and angular bracket members connecting opposite side wall portions of said tube sections to said shoe, said tube sections being compressed between the angular bracket members and the side wall members of said housing.

7. A rubbing machine comprising a housing having side wall members framing an open end, a rubbing shoe positioned over the open end in spaced relation thereto, a power driven shaft extending in said housing and terminating short of said shoe, a fixed shaft extending from said shoe into said housing in offset relation to said power driven shaft, 9. counterweighted eccentric connecting said shafts whereby said shoe is vibrated upon rotation of said power driven shaft, independent flexible connections between marginal portions of said shoe and the side wall members of said housing adjacent said opening for limiting the vibrational movement of said shoe, said flexible connections comprising peripherally spaced tube sections of rubber hose material arranged in pairs at opposite ends of said casing, fastener members connecting side wall portions of said tube sections to the internal surfaces of the side wall members of said housing and U- shaped bracket members connecting the opposite side wall portions of pairs of said tube sections to said shoe.

8. In a rubbing machine having an oscillating rubbing shoe, a supporting housing having peripheral side walls and a power driven shaft extending into said housing,v an eccentric connection between the driven shaft and the shoe for oscillating the shoe, a plurality of flexible, tubular connecting members having side wall portions secured to adjacent peripheral side wall portions of the housing,

and U-shaped bracket members each having the legs thereof secured to opposed side wall portions of a pair of said connecting members and having the bight portion thereof secured to an end of said shoe.

References Cited in the file of this patent UNITED STATES PATENTS George Mar. 12, Kehle Mar. 11,

: Kehle Jan. 20, Champayne Jan. 23, Crosby Mar. 20, Happe Aug. 12,

' Atkin May 26, Champayne Feb. 23,