US3188873A

US3188873A - Adjustable oscillating means

Info

Publication number: US3188873A
Application number: US154643A
Authority: US
Inventors: Kennison L Vowell; Martin E O'dor
Original assignee: North American Aviation Corp
Current assignee: North American Aviation Corp
Priority date: 1961-11-24
Filing date: 1961-11-24
Publication date: 1965-06-15
Anticipated expiration: 1982-06-15

Description

June 15, 1965 vowELL ETAL 3,188,873

ADJUSTABLE OSCILLATING MEANS 3 Sheets-Sheet 1 Filed Nov. 24, 1961 INVENTORS KENNISON L. VOWELL MARTIN E. ODOR 9 X Q.B

ATTORNEY June 15, 1965 K, L. VOWELL ETAL 3,188,873

ADJUSTABLE OSCILLAI'ING MEANS 3 Sheets-Sheet 2 Filed Nov. 24, 1961 KENNISON L. VOWELL BY MARTIN E. O'DOR June 1965 K. L. VOWELL ETAL 3,188,873

ADJUSTABLE OSCILLATING MEANS '3 Sheets-Sheet 3 Filed Nov. 24, 1961 FIG.6

FIG. 7

INVENTORS KENNISON L. VOWELL BY MARTIN E. o'ooa United States Patent 3,188,873 ADJUSTABLE OSCILLATING MEANS Kennison L. Vowell, Los Angeles, and Martin E. ODor,

Downey, Califl, assignors to North American Aviation, Inc.

Filed Nov. 24, 1961, Ser. No. 154,643 9 Claims. (Cl. 74-50) This invention relates to conversion of rotary motion into oscillating movement by means permitting variation of the speed and traversing range of such movement. More particularly, this invention concerns a device of the stated type in extremely small, lightweight and compact form adapted for use in oscillating a miniature welding head although the teachings herein are applicable to oscillating movement for a variety of diverse purposes and devices.

It is a principal object of this invention to provide improved oscillating means capable of adjustment to any amount of reciprocating movement within the limit of its total range of movement for use in converting rotary motion into oscillating substantially linear movement.

It is a further object in this case to provide improved oscillating means characterized by relatively small size and light weight.

It is another object of this invention to provide improved means as set forth in these objects for oscillating a lightweight welding head.

Other objects and advantages will become apparent upon a close reading of the following detailed description of the inventive concept, reference being had to the accompanying drawing wherein:

FIGURE 1 shows in perspective an exploded view of the oscillating mechanism of this invention,

FIGURE 2 shows a cross-sectional view of the oscillating mechanism of FIGURE 1 in the assembled condition,

FIGURES 3, 4 and 5, are cross-sectional views taken along line 3-3 indicated in FIGURE 2 and showing the absence of linear movement resulting from rotation of the parts within the mechanism of FIGURE 2 during one position of oscillating range adjustment knob 78.

FIGURES 6 and 7 are cross-sectional views taken through the structure of FIGURE 2 in a manner similar to FIGURES 3, 4 and 5, showing the different amounts of oscillating movement resulting from two different positions of knob 78 other than the position shown by FIGURES 3, 4 and 5.

Referring to the drawings, the invention disclosed herein may be seen to comprise an oscillating motion converter mechanism 4 which is adapted to be rigidly mounted from suitable supporting structure and to be operatively related to a tool to be oscillated such as a welding torch or electrode.

The oscillating mechanism may be secured on any suitable supporting bracket by means of threaded shaft 2t and a nut engaged thereon. To effectively utilize the oscillatory motion of mechanism 4 output shaft 3% is adapted to be connected at pivot 28 to a suitable lever or bellcrank which is in turn adapted to hold the tool or object to be oscillated.

Referring to FIGURES 1 and 2 the oscillating system may be seen to include a mounting platform 32 upon which a suitable drive motor and the converter mechanism 4 are mounted and operativcly related by driving connection protected by a housing 34 also mounted on platform 32. The stated connection may comprise appropriate gears or other means, and in the illustrative embodiment disclosed herein comprises a pair of pulleys, one of which is shown at 36, connected to the motor and converter mechanism 4, respectively, whereby driving Patented June 15, 1965 power is transmitted through a belt 38 shown more particularly in FIGURE 2. Pulley 36 is secured to end portion 46 of a shaft 42 rotatably journaled within a pair of

bushings

44 and 46 mounted on platform 32 which engages a housing 70 and contacts a spacer ring 47 as shown in FIGURE 2.

Shaft 42 is provided with an annular flange 48 from which a pin 50 downwardly depends whereby pin 50 describes a circle when shaft 42 is rotated. Thus, shaft 42, flange 48 and pin 50 comprise a crank. Pin 50 is operatively engaged within as slide or bearing block 52 of substantially square shape with a round hole centered therein. Bearing block 52 is received within guide means in the form of a cross slot 54 formed on the upper face of a slide block 56. Block 56 is received in a guide groove dd of stationary guide or control means 60 having a slot or aperture 62 centrally located through the bottom thereof. Slide block 56 is formed with a central pin 64 downwardly depending from the lower surface thereof as shown by FIGURE 2 for extension through slot 62 in stationary guide means 66. Pin 64 engages link means by appropriate connection such as opening 66 in one end of output shaft or link 30. Output shaft 30 passes through an opening 68 in the side of a housing 70 within which the internal parts of converter mechanism 4 are enclosed.

The amount of oscillating movement of output shaft 35) resulting from operation of the drive means may be varied from a minimum of zero to a maximum limit as explained more particularly below by adjustment of stationary guide or control means 60 which is provided with a threaded hole 72 at the periphery thereof as shown by FIGURE 1. Threaded shaft 74 engages hole 72 and extends externally from housing 79 through a slot 76 in the housing. A knurled thumbscrew 78 threadedly engaging shaft 74 may be rotated to apply force to spacer 8h bearing against the external surface of housing 7t). Thus, when thumbscrew 78 is rotated to remove clamping force from spacer 8i lateral force applied to shaft 74 may cause rotation of stationary guide member 69 due to the operative engagement of shaft 74 within hole 72. Appropriate markings may be provided on the outer surface of housing 70 as shown at 82 to indicate the relative position of adjustment.

Operation Operation of converter mechanism 4 will be described in connection with FIGURES 3 through 7 showing a plan view of the internal parts looking downwardly from a plane taken through pin 50 as indicated by line 3-3 in FIGURE 2. As mentioned in connection with FIG- URES 1 and 2 discussed above, pin 50 rotates in a circle of constant radius about a relatively stationary center located on the longitudinal axis of shaft 42 in response to rotation of pulley 36 by operation of the drive motor. The rotating movement of pin 50 is indicated by a circle of arrows in each of FIGURES 3 through 7 showing the motion of pin 50 which appears in cross-section.

Referring specifically to FIGURES 3 through 5, inclusive, operation of converter mechanism 4 may be seen during one position of adjustment of knob 78. The stated position of adjustment is in idling position wherein rotation of pin 50 produces no linear oscillations of pivot point 28 at the outer distal end of output shaft 30. Thus, it may be seen from FIGURE 3 that line 82 connecting pivot center 28 with the center of rotation 86 of the circle described by movement of pin 50 is perpendicular to line 84. Line 84 is the center of guide groove 58 within which sliding block 56 moves in a path coinciding with the stated centerline. Inertia effects of the pivotal support of the bellcrank or lever to which shaft 30 may be connected at 28 and the tool operatively attached to such bellcrank or lever are sufficient to hold pivot axis 23 stationar inthe operating condition shown by FIGURES 3, 4 and 5, from which it may be seen that rotation of pin 59 will cause vertical movement of bearing block 52 Within crossslot 54, and horizontal movement of sliding block 56 within groove 5%. Since groove 53 restricts sliding block 56 so as to permit its movement only along line 84, central pin 64011 the bottom of member 56 can also move only along a patlrcoinciding with line 84. Pin 64 extends through slot 62 as'stated above in connection with FlGURES 1 and 2, whereby pin 64 is connected at hole do to output shaft 3%., Accordingly, movement of pin 64 alternately toward the left and right as seen in FlGURE 3, for example, while pivot axis 28 remains relatively stationary as mentioned above, results in angular deviation of the longitudinal axis'of output shaft 30 on either side of line 82, asshown by comparison of FIGURES 3 and 5, but no significant linear movement of output shaft 30.

While the particular structural details set forth above and in thedrawings are fully capable of attaining the objects and providing the advantages hereinstated, the structure thus disclosed is merely illustrative and could be varied or modified to produce the same results Without departing from the scope of the inventive concept as defined in the appended claims.

We claim: V

1. Converter mechanisnrfor converting rotary motion into oscillating linear motion comprising drive means for causing rotational movement of a shaft, oil-center con- 7 nection means on said shaft adapted to describe a circle during said shaft rotation, first sliding block 'means'operatively engaging said connection means for corresponding circular movement of said first sliding block means,

second sliding block means having a groove therein for guiding contact with opposite sides of said first sliding block means so that said first sliding block means is slidably movable relative to said second block means Within said groove, guide means having a groove'therein for.v guiding contact with said second sliding block means so that said second sliding blockmeans is slidably movable with respect to said guide means, said groove in said guide 7 means being situated at an angle with respect to said grooved in said second sliding block means so that oscillating linear movement of said first sliding block means occurs with respect to said second sliding block means and oscillating linear movement ofsaid second sliding block means occurs with respect to said guide means during circular movement of said connection means, and shaft means operatively connected to said second sliding block tance from the axis of said rotation, a first sliding member 7 operativcly engaging said pin for circular motion therewith during rotation of said crank means, a second sliding member adapted to constrain said first sliding member and permitting movement of said first sliding member along a first line of motion with respect to said second sliding member, guide means for constraining said second sliding member'and permitting movement of said second sliding member along a second line of motion with respect to said guide means, and link means including a link operatively connected to said second sliding member for oscillating movement of said link during rotation of said crank means. V

3. The structure set forth in claim 2 above, in which said guide means is adjustably movable to alter the an- 4, movement between two extreme positions, in one of which said first line of motion is perpendicular to said second line of motion, and in the other of which said first line of motion coincides with said second line of motion, and said link is operatively related to.said secondv sliding memoer whereby reciprocating movement of said second sliding member along said second line of motion produces no linear oscillation of said link when said first and second lines of motion are perpendicular to each other, and

produces the maximum linear distance of oscillation of said link when said first and second lines of motion coincide with each other. V

5. In lightweight, compact apparatus for converting rotational movement to reciprocating movement; rotatable crank means, relatively stationary control means, a slide block disposed' between said crank means and said control means, a slidable driving member connecting said crank means and said slide block whereby linear movement of said driving member occurs relative to said slide block, and said movementof said drivingmember is limited along a first line perpendicular totthe turning axis of said crankmeansduring rotation of said crank means, said control means having motion guiding means thereon for limiting sliding movement of said slide block along a second line of motion, and link means operatively connected to saidslide block whereby reciprocating movement of said slide block causes oscillation of said link means.

6. The apparatus set forth in'claim 5 above wherein said control means is rotationally adjustable to vary the direction of said second line of motion whereby the linear distance traversed by said link means during said oscillation thereof may be varied from zero when said first and second lines are perpendicular to a maximum when said first and second lines coincide.

7. In lightweight, compact apparatus for converting rotational movement to reciprocating movement; a housing, drive means'external ofsaid housing and rotatable with respect thereto, crank means including'a shaft supported within said housing and connected to said drive 7 means for rotation therewith, said crank means further gular relationship between said first and said second lines ment of said link is adjustably variable.

4. The structure set forth in claim 3 above wherein said guide means adjustability consists of rotational including a pin offset at a distance from the axis of location of said crank means, a first slide block pivotally engaging said; pin whereby'said pin and said first slide block describe a circle having a radius equal to said offset distance, a second slide block having a groove therein for guiding contact with said first slide block whereby linear movement of said first slide block'occurs relative to said second slide block along a line perpendicular to the axis of rotation of said crank means during said circular movement of said first slide block, a guide block within said housing, said guide block having a groove therein for guiding Contact with said second slide block whereby linear movement or" said second slide block occurs relative to said guide block along a second line lying at an angle to said first line, and link means including a link operatively connected to said second slide block whereby movement of said second slide block within said housing is transmitted to a location external or" said housing.

8. The structure set forth in claim 7 above including in addition thereto, adjustment meansfor adjustably rotating said guide block with respect to said housing to change the angularity between said first and second lines whereby the linear distance traversed by said link is adjustably variable from aminimum of zero when said first and second lines are mutually perpendicular to a maximum when said first and second lines coincide.

9. In apparatus for converting rotating movement to reciprocating movement: rotatable crank means having an ofi-center pin on said crank means located at a distance from the axis of said rotation, a first sliding member operatively engaging said pin for circular motion therewith during rotation of said crank means, a second sliding member adapted to constrain said first sliding 3,188,873 5 6 member and permitting movement of said first sliding References Cited by the Examiner member along a first line of motion with respect to said UNITED STATES PATENTS second sliding member, stationary guide means for constraining said second sliding member and permitting 2,838,956 6/ 5 8 Schneider 74' 571 XR movement of said second sliding member along a second 5 2932355 4/60 Nelklrch 74-600 XR line of motion with respect to said stationary guide means, FOREIGN PATENTS and link means including a link operatively connected to said second sliding member for oscillating movement of 1O05801 4/57 Germany said link during rotation of said crank means. BROUGHTON G. DURHAM, Primary Examiner.

Claims

1. CONVERTER MECHANISM FOR CONVERTING ROTARY MOTION INTO OSCILLATING LINEAR MOTION COMPRISING DRIVE MEANS FOR CAUSING ROTATIONAL MOVEMENT OF A SHAFT, OFF-CENTER CONNECTION MEANS ON SAID SHAFT ADAPTED TO DESCRIBED A CIRCLE DURING SAID SHAFT ROTATION, FIRST SLIDING BLOCK MEANS OPERATIVELY ENGAGING SAID CONNECTION MEANS FOR CORRESPONDING CIRCULAR MOVEMENT OF SAID FIRST SLIDING BLOCK MEANS, SECOND SLIDING BLOCK MEANS HAVING A GROOVE THEREIN FOR GUIDING CONTACT WITH OPPOSITE SIDES OF SAID FIRST SLIDING BLOCK MEANS SO THAT SAID FIRST SLIDING BLOCK MEANS IS SLIDABLY MOVABLE RELATIVE TO SAID SECOND BLOCK MEANS WITHIN SAID GROOVE, GUIDE MEANS HAVING A GROOVE THEREIN FOR GUIDING CONTACT WITH SAID SECOND SLIDING BLOCK MEANS SO THAT SAID SECOND SLIDING BLOCK MEANS IS SLIDABLY MOVABLE WITH RESPECT TO SAID GUIDE MEANS, SAID GROOVE IN SAID GUIDE MEANS BEING SITUATED AT AN ANGLE WITH RESPECT TO SAID GROOVED IN SAID SECOND SLIDING BLOCK MEANS SO THAT OSCILLATING LINEAR MOVEMENT OF SAID FIRST SLIDING BLOCK MEANS OCCURS WITH RESPECT TO SAID SECOND SLIDING BLOCK MEANS AND OSCILLATING LINEAR MOVEMENT OF SAID SECOND SLIDING BLOCK MEANS OCCURS WITH RESPECT TO SAID GUIDE MEANS DURING CIRCULAR MOVEMENT OF SAID CONNECTION MEANS, AND SHAFT MEANS OPERATIVELY CONNECTED TO SAID SECOND SLIDING BLOCK MEANS FOR TRANSMITTING SAID MOTION OF SAID SECOND SLIDING BLOCK MEANS TO MOVABLE STRUCTURE FOR CAUSING OSCILLATING MOVEMENT OF SAID MOVABLE STRUCTURE.