Obstacle type switch detent
US 3126758 A
Description (OCR text may contain errors)
March 31, 1964 w, MARTlN 'ETAL 3,126,758
OBSTACLE TYPE SWITCH DETENT Filed Dec. 19, 71960 F|G.l 2s 24 22 FIG-2 24 54 INVENTORS DONALD W. MARTIN ROBERT F. UBELHOER JAMES S- ARWICK OR NEY United States Patent 3,126,758 OBSTACLE TYPE SWETQH DETENT Donald W. Martin, St. Paul, and James S. Warwick and Robert F. Uhelhocr, Minneapoiis, Minn, assignors to Sperry Rand Corporation, New York, N.Y., a corporation of Delaware Filed Dec. 19, 1960, Ser. No. 76,801 Claims. (Cl. 74565) This invention relates to manually operated switch controllers generally, and more specifically to a provision within the switch controller of detent positions that are mechanically linked to certain contact positions within a contact assembly so that a releasable locking engagement occurring in the detent positions prevents rapid shifting from one contact position to the next contact position in the assembly.
In some applications of a multi-position switch it is advantageous to prevent an operator from proceeding rapidly and continuously from one switch position to another. For example, in certain types of power supply devices, it is desirable to be able to bring each power supply chassis up to full operation separately in a step-bystep process with a delay between each step. It could, therefore, be a requirement that the operator hesitate or be positively retarded in the action that would actuate the switch to its next position.
The present invention, although quite simple in construction, performs with a high degree of reliability, and permits a manual operation to be accomplished in a positive manner thus avoiding the possibility of failure that may occur if a time delay were accomplished by electromechanical means.
It is accordingly an object of the invention to provide an improved switch controller with a means to positively prevent a rotary type switch from being turned from one position to another too rapidly.
It is another object of this invention to provide means for preventing an operator from turning a rotary type switch from one position to the next in a time interval of less than approximately one second.
A further object of this invention is to provide means to constrain undesirable motion of a detent member.
A still further object of this invention is to provide a simplified switch controller mechanism, so that component parts thereof may have broad tolerances thereby providing economy of construction and ease of maintenance.
These and other more detailed and specific objectives will be disclosed in the course of the following specification, reference being had to the accompanying drawings, in which:
FIGURE 1 is a side elevation view having a portion thereof cut away to more clearly illustrate a switch controller in combination with a rotary switch assembly.
FIGURE 2 is a longitudinal sectional view taken in the direction of the arrows along the line 22 of FIG- URE 1.
FIGURE 3 is a detail view of the detent ring depicting a groove therein.
FIGURE 4 is an enlarged view of one S-shaped section of the groove in FIGURE 3.
Referring now to FIGURE 1 there is shown a switch controller having a contact assembly 32 which is of the rotary type and of usual design and construction. A shaft 20 having a handle 28 attached to one end thereof, passes through appropriate apertures in the front housing plate 22, the rear housing plate 26 and centrally through the housing ring 24. The housing plates 22 and 26 are attached to the housing ring 24 by screws 25 and 27 while the contact assembly 32 is attached to the annular housing ring 23 by screws 35. The ring 23 is attached to housing "ice plate 26 by screws best been in FIG. 2. One end of the shaft 20 is formed with a semi-circular cross section or flat 21 over a predetermined length thereof and mates with a bar 30. The mating surfaces are held in contact with one another by a sleeve 3i which circumferentially surrounds them, as shown in the cutaway section of FIG- URE 1. It is a result of this mating that motion of the shaft 2%) is transmitted to operate the contacts within the contact assembly 32. In this embodiment the contact assembly 32 is shown as comprising a rectangular frame in which are located the contacts which have the appropriate extensions for the usual circuit connections. The circuit through the contacts is arranged to be completed by the contacts opening or closing in response to the positioning of the shaft 20.
FIGURE 2 shows that the shaft 20 is disposed through a metal disk member 34 which has a central aperture to receive the shaft and a recess to accept a Woodruff key 36. The key 36 lies in a complementary recess in the shaft 20 thereby connecting the shaft to the disk member 34. Extending radially from the disk member 34, and essentially a projection thereof, is a pin or detent means 52, the purpose of which will be hereinafter explained. The disk member 34 is held in place on the shaft 20 between a retaining ring 38 and a flange 4t). Yieldably urging the shaft outwardly is a helically wound spring 42 which is confined between the flange 40 and a retaining ring 44 which is seated in a recess on an insert 46. Attached by pins 56 to the inner wall of the housing ring 24 is a detent ring or annular sleeve 48 which has a groove 54 extending circumferentially in a serpentine pattern about the inner periphery of the housing ring 24 and having abrupt or retrograde portions at 56. The detent ring 48 is composed of two separate annular pieces of metal with recesses machined in an edge of each, such that when the edges of the pieces are placed face to face the recesses are complementary and the groove 54 results. Slidably received by the groove 54 is the pin 52. Because of the serpentine pattern described by the groove 54, the motion of the pin 52 within the groove 54 is inhibited by the interaction of the pin 52 with the groove wall 56 as will become apparent. This interaction causes a locking or detent action and where this interaction occurs, there results a detent position which is mechanically related to an appropriate switch position within the contact assembly 32.
The detent is effective to constrain undesirable motion of the pin 52 in a manner that will permit desirable motion thereof if a proper combination of forces is applied to the shaft 20.
FIGURE 3 depicts the configuration of the groove 54 which is seen as a continuous series of substantially S- shaped sections. There can be seen two axial gradients the first of which is longer than the second. The axial gradients form a continuous groove when an arcuate end wall is disposed to merge into the two axial gradients. It is the purpose of these peculiar sinuous sections to retard and limit axial movement of the shaft 20 and to require alternate clockwise and counter clockwise rotation of the shaft in order to step the switch contacts from one position to an adjacent position. FIGURE 3 also shows the start and terminal position of a series of switch positions and indicates that there are several other switch positions. In the instant embodiment, although they are not all shown by the figures, there are fourteen switch positions which correspond to contact positions within the contact assembly 32.
To operate the contacts located within the contact assembly 32, the shaft 20 is rotated and simultaneously pushed inwardly by pressure on the handle 28. The inward direction is designated by the arrow 33 seen on FIGURE 3. In effect, the operator must, by moving the showing the pin 52 in various positions and indicating by the arrows the direction in which the shaft 20 must be rotated to move the pin 52 from the detent position identified as position A to the detent position A of the next section. The arrow as shown at A indicates that the shaft 20 must be rotated in a clockwise direction and, as previously mentioned, this motion must be accompanied by inward pressure upon the shaft 20. The combination of these two motions will progress the pin 52 to the position B. Further clockwise rotation of the shaft 29 is impossible for the pin 52 is at this point caused to abut the groove wall 56. Therefore, the operator must, while continuing inward pressure upon the shaft 20, now rotate it in a counterclockwise direction, and thus the pin 52 will proceed to position C where it will again bear against the groove wall 56 and inhibit counterclockwise rotation of the shaft. As indicated by the arrow at C, the operator must now rotate the shaft in a clockwise direction while simultaneously applying an inward pressure upon it. The pin 52 will thereby proceed to position D where it will again bear upon the groove wall 56 and resist inward pressure upon the shaft 2% Rotation of the shaft is not inhibited in this inward axial position and as the operator continues to rotate the shaft, he is required to release inward pressure upon it. The spring 42, compressed by the inward pressure upon the shaft 20 as it traveled to its limiting inward axial position D, now urges the shaft outwardly. The pin 52, guided by the camming action of the groove 54, reaches position A as a result of the clockwise rotation of the shaft 20 and the concurrent urging outwardly of the shaft 20 by the spring 42. When the pin 52 reaches the position A it will abut the groove wall 56 and prevent further outward axial movement of the shaft 20. Clockwise rotation of the shaft 20 may be continued if accompanied by an inward pressure. If no inward pressure is exerted, a locking engagement dev'elops inhibiting further rotation. Rotation of the shaft 20 in either direction is inhibited by the pin 52 striking the groove walls 56. Axial motion is prevented for the same reason, if the shaft 20 is not rotated. Therefore, requiring the pin 52 to traverse a certain distance in the above described manner and under the impetus of a combination of forces, has effectively caused a desirable time delay and prevented too rapid switching from one contact to another. Because it is a requirement that the shaft 20 be rotated and moved axially simultaneously before motion of the pin 52 in the groove 54 can occur a detent action results if either rotational or axial motion or both are omitted.
It is understood that suitable modifications may be made in the structure as disclosed provided such modifications come within the spirit and scope of the appended claims. Having now, therefore, fully illustrated and described our invention, what we claim to be new and desire to protect by Letters Patent is:
1. In a switch controller, detent means for correlation with a plurality of switch positions, an axially movable and rotatable shaft, an outwardly extending member attached to said shaft, said detent means comprising an annular sleeve disposed about said shaft and having a circumferentially-extending inwardly-opening recess slidably engaging the outwardly extending member, said recess having a sinuous angular configuration in an axial direction and the recess being shaped such that as the shaft is rotated in a first direction there is an interengagement of the wall of said recess with the extending member so as to require a reversal of rotation with a concurrent axial movement for permitting further rotation in said first direction.
2. In a switch controller, a shaft member having a radially outwardly extending detent means, a sleeve member disposed about the shaft member and having a circumferentially extending and radially inwardly opening groove which movably receives the means, the two members being coaxial and being axially and rotatably movable about the axis with respect to each other, the groove having a plurality of axially extending portions which circumferentially and alternately lie in opposing circumferential directions to cause the relative rotation of the members to stop.
3. Apparatus as in claim 2 wherein said groove has an axial asymmetrial sinuous configuration.
4. In a switch controller, a frame, a manually axially movable and rotatable shaft having two axial limit positions and movably mounted on said frame, spring means within said frame and disposed about said shaft for yieldably urging said shaft into a first of the two positions, a radially-outwardly extending pin mounted on said shaft, an annular sleeve on the frame and disposed about said shaft and Having an axially undulating and radially-inwardly-opening circumferentially-extending groove, said groove slidably receiving said pin, the groove consisting of a plurality of alternating first and second sections, each first section being elongated with a first axial gradient, each second section being the shorter one of the two and having a second and greater axial gradient and at least one arcuate and end wall facing into an adjacent first section, and said arcuate end wall being engageable with the pin as the shaft rotates for at least momentarily stopping rotation of the shaft.
5. In a switch controller having a detent for correlation with a switch position, an axially movable and rotatable shaft movable between two predetermined axial positions, an outwardly extending member connected to said shaft, an annular sleeve disposed about said shaft and having a circumferentially-extending inwardly-opening recess slidably engaging the outwardly extending member, said recess describing an axial serpentine path with directional reversals for causing interengagement of the extending member and a wall of said recess so as to require alternately a combined axial movement and rotational movement in a first sense of the shaft and a combined axial movement and rotational movement of the shaft in a second sense for moving the shaft between the axial positions.
References Cited in the file of this patent UNITED STATES PATENTS 1,391,948 Gledhill Sept. 27, 1921 1,794,234 LeFrancois Feb. 24, 1931 2,453,187 Blain Nov. 9, 1948 FOREIGN PATENTS 420,009 France Nov. 11, 1910 4,934 Netherlands May 15, 1920 207,922 Great Britain Dec. 13, 1923