US2247792A - Operating mechanism - Google Patents

Description

July 1, 1941. A. G. STIMSON I I OPERATING MECHANISM Filed July 24, 1940 Invent or Al len G. sbinfison,

by F

. His Attorney Patented July 1, 1941 OPERATING MECHANISM Allen G. Stimson, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application July 24, 1940, Serial No. 348,971

5 Claims.

My invention relates to operating mechanism and has for its object simple and reliable mechanism for converting the rapid movement of a solenoid or other member having rectilinear movement to a movement having an initial and final slow movement and having no inoperable dead center positions.

A solenoid armature has the characteristic of accelerating very suddenly when it starts to move and continuing at top speed until it is suddenly brought to a stop at its limit of travel. This characteristic of operation results in some cases in objectionable jars and strains on the apparatus being operated. It is an object of my invention to provide mechanism for converting this sudden high speed movement to a movement having a comparatively slow acceleration and deceleration.

In carrying out my invention, I provide an operating linkage between the solenoid armature and the device operated by it, which linkage comprises a rotatable member connected to the part operated and arranged to be in substantially dead center positions at the limits of travel.

For a more complete understanding of my invention, reference should be had to the accompanying drawing, the single figure of which shows an operating connection for a solenoid embodying my invention.

eferring to the drawing, I have shown my invention in one form as forming an operating connection between a solenoid armature I and the operating lever I I of a counting or registering device I2. The connection comprises a lever or bell crank arm I 3 having a fixed pivot I4 and connected to the armature It by means of a link I5 having pivot connections I6 and IT with the lever I3 and armature respectively. The end of the lever i3 is connected through a link I8 to an arm I9 secured to a shaft mounted in suitable fixed bearings, the link I8 having pivotal connections 2I- and 22 with the arms I3 and I9 respectively. A link 23 is pivotally attached at one end to the pivot pin. 22 and at the other end pivotally to the end of the arm I I.

For the purpose of biasing the parts normally to the position shown, a helical spring 24 is provided surrounding the shaft 20 and having one end 25 engaging the fixed pivot I4 and its other end 26 in engagement with the pivot pin 22.

This spring is biased to coil itself; in other words, as shown, the ends of the spring are forced apart by the shaft I4 and pivot 22 so as to uncoil the spring somewhat, the spring applying a force tending to turn the arm I9 in a counterclockwise direction, as shown in the drawing, about the shaft 20 and thereby through the link I3 turning the arm I3 in a counterclockwise direction to the position shown in the drawing. This raises the armature III to the position shown, it being assumed that the operating coil 21 for the armature is deenergized.

In the construction of this mechanism, the relation of the lengths of the arms I3 and'l9 and the distance between the axes of the shafts I4 and 20 is important. Preferably the sum of the length of the arm I9 and the distance between the axes of the shafts I4 and 20 is equal to or less than the length of the arm I3, 1. e., the distance between the axis of the shaft 54 and the axis of the pivot 2i. As shown in the drawing, the sum of these two distances is equal to the length of the arm I3, the arc of movement of the arm I3 indicated by the dotted line 28 being tangential to and outside of the arc of movement of the axis of the pivot 22 indicated by the dotted line 29. Also, as shown in the drawing, the link I8 is of such length that the link I8 is at a substantial operating angle with the arm 19 throughout the substantially 180 degrees movement of the arm I9. Because of this substantial operating angle the link I8 applies a substantial component of its force in a direction to turn the arm I9 about its pivot 26. As shown with the arm IS in one of its extreme positions, the angle between the link I8 projected and the arm I9 is substantially degrees. This angle increases with clockwise movement of the arm I9 to substantially degrees and then decreases to substantially 45 degrees when the arm I9 is in its other extreme positions degrees from the position shown in the drawmg.

As a result of this arrangement, the arm I9 is rotated through substantially 180 degrees, the lower arm I3 being rotated through a much smaller angle, when the coil 21 is energized and the armature Ill pulled downward to its attracted position. In other words, the pivot 22 shown substantially directly below the shaft 20 is then substantially directly above the shaft 28. In each of these limiting positions it will be observed that the pivot 22 is in a substantially dead center position both with respect to the direction of movement of the armature II] and the direction of movemnt of the link 23 in operating the device I2. Thus when the coil 2'! is energized, the armature, even though its movement is rapid, at first imparts a relatively slow vertical movement to the link 23, which movement increases in velocity and reaches the maximum velocity at substantially the midposition of the movement of the arm l9, i. e., when the arm is substantially horizontal, as seen in the drawing. Thereafter, as the arm l9 continues its movement upward in a clockwise direction, the vertical component of the velocity of the link 23 decreases and it is brought gradually to rest.

A suitable support 30 is provided for the shafts M and 20 and the other parts. The pivot 22 is preferably extended to provide for connection with the link 23. Also suitable stops (not shown) are provided for limiting the movement of the parts with the armature in its attracted and unattracted position. For example, the armature H3 may be provided with stops limiting its movement in each direction or the support 39 may be provided with projections to engage the pivot 22 in each of its limiting positions.

While I have shown a particular embodiment of my invention, it will be understood of course that I do not wish tobe limited thereto, since many modifications may be made and I therefore contemplate by'the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. The combination with a member having rectilinear movement of a lfirst arm having a fixed pivot, a connectionbetween said first arm and .said member for movement of said arm through a predetermined a-rc upon movement of said member between two positions, a second arm having a fixed pivot, and a link connecting said arms to each other, the point of connection of said link with said first arm having a radius of movement greater than the radius of movement of the point of connection of said link with said second armso that the arc of movement of said first arm is at least substantially outside of the arc of movement of said second arm.

2. The combination with a member having rectilinear movement of a first arm having a fixed pivot, a connection between said first arm and said member for movement of said arm through a predetermined are upon movement of said member between 'two positions, a second arm having a fixed pivot, and a link connecting said arms to 'each other, the point of connection of said link with said first arm having a radius of movement greater than the radius of movement of the point of connection of said link with said second arm so that the arc of movement of said first arm is at least substantially outside of the arc of movement of said second arm and said link being of such length that said link is at a substantial operating angle with said second arm during movement of said second arm.

3. An operating connection between a member having rectilinear movement and a device to be operated comprising two arms pivotally mounted on separate pivots, a link connecting said arms together, one of said armsbeing longer than the other of said arms and arranged so that a predetermined small angular movement of said longer arm moves said shorter arm through a large angle of substantially 180 between two positions, a connection between said shorter arm and the device to be operated, and a connection between said member and said longer arm for movement of said longer arm by said member through said small angle.

4. An operating connection between a member having rectilinear movement and a device to be operated comprising two arms pivotally mounted on separate spaced apart stationary pivots,'a link having its ends pivotally connectedto the ends of said arms so as to connect said arms together,

'one of said arms being longer than the other of'said arms and arranged so that a predetermined small angular movement of said longer arm moves said shorter arm through a large angle of substantially 180 between two positions, a link for connecting the shorter arm to a device to be operated extending in a direction substantially parallel with said shorter arm in each of said two positions, and a connection between said member and said longer arm for movement of said longer arm through said small angle by said member.

5. An operating connection between a member having rectilinear movement and a device to be operated comprising two arms pivotally mounted on separate spaced apart stationary pivots, a link having its ends pivotally connected to the ends of said arms so as to connect said arms together, one of said arms being longer than the other of said arms whereby a predetermined small angular movement of the longer arm moves the shorter arm through a large angle of substantially 180 between two positions and said arms being arranged and said link being of such length that said link is at a substantial operating angle with said shorter arm throughout said 180 movement of said shorter arm, means connecting the shorter arm to a device to be operated, and a connection between said member and said longer arm for movement of said longer arm through said small angle by said member.

ALLEN G. STIMSON.

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