US3727482A

US3727482A - Automatic locking control device

Info

Publication number: US3727482A
Application number: US00153176A
Authority: US
Inventors: L Geer
Original assignee: Adams Rite Manufacturing Co
Current assignee: Adams Rite Manufacturing Co
Priority date: 1971-06-15
Filing date: 1971-06-15
Publication date: 1973-04-17
Anticipated expiration: 1990-04-17
Also published as: CA956145A; GB1384011A

Abstract

An irreversible control device in which an input member is connected with an output member through a locking element which is fulcrumed on a fixed locking bar for swinging movements to locked and unlocked positions respectively with the locking bar, and is normally spring-urged into an unlocked position which permits the output member to be moved freely to different positions of adjustment in response to selective movements of the input member, but in an adjusted position will be fulcrumed to a locked position on the bar in response to an attempted movement of the output member away from its adjusted position by reverse operation by means of the output member.

Description

United States Patent Geer 1451 Apr. 17, 1973 Primary Examiner--Milton Kaufman Attorney-Whann & McManigal 5 7 ABSTRACT An irreversible control device in which an input member is connected with an output member through a locking element which is fulcrumed on a fixed locking bar for swinging movements to locked and unlocked positions respectively with the locking bar, and is normally spring-urged into an unlocked position which permits the output member to be moved freely to different positions of adjustment in response to selective movements of the input member, but in an adjusted position will be fulcrumed to a locked position on the bar in response to an attempted movement of the output member away from its adjusted position by reverse operation by means of the output member.

15 Claims, 5 Drawing Figures AUTOMATIC LOCKING CONTROL DEVICE BACKGROUND OF THE INVENTION The invention relates generally to irreversible locking control devices.

Heretofore, one type of device of this character has been generally known and exemplified in U. S. Pat.

' Nos. 2,703,499 and 2,895,347. The control arrangements disclosed in these patents are basically similar and utilize a pair of locking elements which are respectively pivotally mounted on an output member for pivoted swinging movement thereon into locking engagement with a common locking bar, the locking elements being normally spring-urged in opposite directions about their pivot mounting into locking positions with the locking bar. These locking elements normally act to retain the output member against movements by an applied force thereon. A swingably pivoted input adjusting lever is arranged, however, to release the locking elements and permit adjusting movements of the coupled output member.

A more recently known device in this field is a structure as embodied in control levers presently being sold by Adams Rite Manufacturing Company under its Trademark QUADRASTAT and identified by this company as its Models 3800, 3801 and 3850.

These control devices, instead of utilizing a pair of normally locked locking elements in the manner disclosed in the foregoing noted patents, and which require a secondary unlocking motion before the adjusting operations of the output member can be accomplished, make use of a single locking element which normally bears against one side of the locking bar at a single point of contact and carries spaced apart contacts on the opposite side of the bar which are normally in disengaged positions with reference to the bar. Thus, the locking element-is freely movable along the bar to effect adjusting movements of the output member. The arrangement is such, however, that when the locking element is tilted or fulcrumed in one direction or its opposite direction with reference to the initial point of contact by a feed-back force applied to the output member, one or the other of the spaced contacts will coact with one or the other of two newly established bar gripping points that are positioned outwardly from the single initial point of contact. The transition from one of these newly established points to the other produces an undesirable lost motion or backlash. It is therefore a general feature of the present invention to improve this later design and provide an arrangement wherein the initial contact point or contact points will be substantially coincident with the newly established points of contact to the end that the adjustments may be accomplished more rapidly and with a minimum and very small amount of lost motion or backlash.

SUMMARY OF THE INVENTION The present invention relates generally to automatic locking control devices, and is more particularly concerned with the provision of control devices of the type which will have improved operating characteristics.

A further object is to provide a locking control device according to the herein. described invention which is of simplified and improved construction, which will have a long operating life, which is easily and quickly adjusted, and which is especially adapted for industrial installations and other situations wherein vibrations may be present and normally constitute an objectionable factor.

A further object is to provide an irreversible locking control device in which the input and output members have a high degree of versatility which permits their connection for widely varying installation requirements requiring different angular positions of the input and output members, as well as adaptability for axial and remote control arrangements.

Another object is to provide an irreversible locking control device in which the locking element is normally freely movable along a locking bar, and which utilizes a unique construction for reducing lost motion or backlash in moving the locking element to a locking position.

Still another object is to provide in such a device a unique spring structure for urging friction shoes into engagement with the locking bar, such spring structure providing a shielding and protective cover over the locking element.

It is also an object of the invention to provide an improved detent at a mid-adjustment position of the device, wherein one of the friction creating members is utilized to seat in an opening of the locking bar at the desired detent position.

Further objects and advantages of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing a preferred embodiment of the invention without placing limitations thereon.

BRIEF DESCRIPTION OF THE DRAWINGS Referring to the accompanying drawings, which are for illustrative purposes only:

FIG. 1 is a front elevation of an irreversible locking control device embodying features of construction according to the present invention;

FIG. 2 is a fragmentary side elevational view of the same;

FIG. 3 is a fragmentary sectional view with portions cut away to reveal certain parts of the device, taken substantially on line 3-3 of FIG. 2;

FIG. 4 is an enlarged fragmentary transverse sectional view, taken substantially on line 4-4 of FIG. 1; and

FIG. 5 is an enlarged fragmentary detailed view illustrating the operative relationship between the locking element and the locking bar.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more specifically to the drawings, there is illustrated in FIG. 1 as generally indicated at 10, an irreversible locking control device which may be mounted upon any suitable type of frame structure, such as a panel surface, frame members, and the like. As illustrated, the device is shown as being attached to an angle mounting bracket 11 as by suitable mounting bolts l2--l2, as shown in phantom lines.

The mounting bolts are shown as connecting a quadrant member 13 to the mounting bracket, this quadrant member being constructed with a straight bar portion 14 which is connected at its ends to an arcuate bar portion which provides a locking bar 15 having an inner edge 16 and outer edge 17, these edges being concentric with respect to a stud or pin 18 which pivotally mounts an input drive member 19 on one side of the bar portion 14, and an output drive member 20 on the opposite side thereof.

As best shown in FIG. 2, the input drive member is formed by stamping or otherwise from a flat metal strap material so as to provide an elongate member with an offset portion 21 adjacent one end which is apertured to receive an end of the pin 18 upon which it is retained by a retaining washer 22 which is secured against a circumferential shoulder 23 by peening over the rivet end, a spacer washer 24 being interposed between the retaining washer 22 and the input drive member. Adjacent the offset portion 21, the input drive member is formed with a channel section 25 having similarly constructed projecting side flanges 26-26. Each side flange is provided with a generally L-shaped slot 27 with an edge opening 28 which permits assembly of the quadrant member 13 with the input drive member 19 and the locking bar thereof freely extending through the slots. The end portions of the input drive member are formed to provide

end lug portions

29 and 30 for the reception of attaching bolts 31-31 by means of which an input lever or handle 32 may be attached. The mounting described permits the handle to be mounted in relatively reversed positions to accommodate the device for different installation requirements.

The output drive member 20 is stamped or otherwise formed from a flat metal sheet to provide a generally T- shaped structure containing a cross-piece 33 and a main leg 34. The input drive member is pivotally mounted at the center of the cross-piece axis upon the head end of the pin 18, and the end portions of the cross-piece 33 are forwardly offset and formed to provide end mounting lugs 35-35, each of these lugs having an aperture 36 therein. These mounting lugs permit the connection of the output drive means to various types of outputs such as an axially aligned shaft (not shown) or to a suitable output lever as generally indicated at 37.

The output lever 37 is provided with anenlarged generally circular portion 38 at one end from which there projects a radially extending arm 39. The circular portion 38 is provided with a plurality of circumferentially spaced openings 40 which permit attachment of this end of the output lever in a multiplicity of angular positions throughout 360 by means of diametrically positioned attaching bolts 41 positioned in the aperatures 36-36 of the mounting lugs 35-35. The radially extending arm 39 is also provided with a plurality of spaced aligned openings 42 which provide a series of connection points for transmitting linkages and the like at different distances from the center of rotation of the output drive member 20.

As best shown in FIG. 3, the leg 34 of the output drive member extends radially from the axis of rotation on the pin 18, and is positioned within the inner end of the channel section 25 for limited oscillatory movement between the side flanges 26-26. The outer end of the leg 34 in the channel section is provided with edge abutments 43-43. 1

The main leg 34 is operatively coupled with the locking bar through a locking element as generally indicated at 44. This locking element is fabricated from a metallic strap into a U-shaped configuration having parallel uniformally spaced leg portions 45 and 46 (FIG. 4) which are interconnected by means of a bridging portion 47. As shown in FIG. 3, the locking element 44 is positioned within the channel section 25 with its legs straddling the locking bar 15 and extending in overlapped relation on opposite sides of the adjacent end of the main leg34 of the output drive member. The legs of the locking element have a width corresponding substantially to the width of the leg 34 between the edges of the abutments 43-43. In the non-locking position the edges of the locking element and the abutments are slightly inwardly spaced from the adjacent side flanges 26-26. As shown, the outer ends of the

leg portions

45 and 46 are connected with the end of the main leg by means of a pin 48 which is guidingly mova-. ble lengthwise of a radially extending rectangular slot 49 provided in the leg 34. A compression loading spring 50 is mounted in the slot 49 with one end bear ing against the pin 48 and its other end bearing against the adjacent end of the slot 49 and acts to radially move the locking element radially inwardly with respect to the locking bar 15 so as to forceably bring the bridging portion 47 into pressure engagement with the-outer edge 17 of the locking bar.

In the position of the locking element 44 as just described, it will be appreciated that the bridging portion 47 has its inner surface, as indicated at 51, extending in a tangential direction to the engaged edge 17. At the inner edge 16 of the locking bar, the locking element is provided with a pair of locking pins 52-52 which are symmetrically spaced on opposite sides of the longitudinal axis of the locking element, and are so arranged that when the bridging portion is normally forced against the edge 17, these locking pins will be I closely spaced bya small clearance with respect to the edge 16. As thus arranged, it will be understood that when the locking element is fulcrumed about the contact engagement of the inner surface 51 with the edge 17, the locking pins will be alternatly brought into locking engagement with the bar, depending upon the direction in which thelocking element is tilted about its fulcrum contact with the edge 17. Assuming that the inner surface 51 is continuous between the edges of the locking element, it will be seen that during a locking operation, the effective contact point on the inner surface 51 will be shifted towards one end or the other of the bridging portion 47. This movement of the locking element from one locking position to the other will obviously be accomplished with an undesirable backlash or lost motion. In order to minimize the backlash 'or lost motion during movements between locking positions, it is an important feature of the present invention to provide a transversely extending slot 53 at the center of the bridging portion in order that closely spaced engagement points, as indicated at 540 and 54b will be established with the edge 17. Moreover, these points of engagement effect in each case both a gripping point and a fulcrum point in such a manner that the gripping operation takes place substantially immediately without noticeable backlash or lost motion. In the arrangement just described, the locking element in its normal position is free for translatory movement along the locking bar 15, but upon slight tilting movement in opposite directions respectively about the fulcrum-contact points 54a and 54b, the locking element becomes securely locked with respect to the locking bar 15.

Since the locking element 44 as embodied in the present invention is normally in a non-locked position with respect to the locking bar 15, it is desirable to provide an appropriate amount of frictional resistance to the translatory movement of the locking element along the locking bar during adjusting movements of the device. This is accomplished by means of a pair of friction shoes or elements as shown at 55 and 56. These elements may vary as to configuration but are illustrated, as best shown in FIG. 4, as comprising cylindrical members which are guidingly supported for axial movements within axially aligned openings 57-57 in the

leg portion

45 and 46 respectively adjacent the bridging portion 47. The confronting ends of the friction elements are arranged to bear against the side faces of the locking bar and are normally springurged against the locking bar by means of a spring member as generally indicated at 58. As shown in FIG. 4, the spring member 58 is of U-shaped configuration with an elongate inner leg 59 which extends along the bottom of the channel section 25 .and is secured thereto as by rivets 60. A shorter outer leg 61 is connected to the leg 59 by a bridging portion 62 and has its outer end bearing against the adjacent end of the friction element 56. The outer end of the friction element 55 bears against the leg 59 the spring member. Balanced frictional forces are thus applied to the opposite sides of the locking bar 15. It will also be observed that by constructing the spring member 58 as thus described, the leg portions and bridging portion of the spring provide a protective cover at the outermost end of the channel section 25.

in some installations, it may be desirable to provide a detent for releasably holding the locking element at a neutral or mid-position of the locking bar 15. This may be done by providing an opening 63 in the locking bar to receive a portion of one or both of the friction elements. in the event that cylindrical friction elements are utilized as shown, the inner ends of the elements may be made frusto-conical as shown in the case of element 56. A ball element may also be used in lieu of the structure shown for the friction element.

Having described the details of construction of the irreversible locking control device of this invention, the operation will now be considered briefly. Assuming that the locking element is in an unlocked position at the detent at the middle of the locking bar 15, or at an adjusted position on the bar, the spring 50 will load the locking element and force it inwardly so that the engagement points 54a and 54b will engage the outer edge 17 of the locking bar. In this position, the locking pins 52 will be disengaged with respect to the inner edge 16 of the lockin bar. The control may now be actuated by moving the input drive member by means of the handle 32 or other connected means, in opposite directions to adjust the position of the output drive member together with the output lever, if an output lever is being utilized, into a desired adjusted angular position. In making this adjustment, the effective flange 26 will be moved to a position which will positively drive and move the locking element and the output drive member as a unit. During this adjustment the locking element is in an unlocked position and moves along the locking bar with a translator movement, this movement being resisted only by the frictional drag which is purposely applied by the friction elements 55 and 56.

At the desired position of adjustment, the applied motivating force is withdrawn, and the applied frictional forces will now tend to normally hold the device in the adjusted position. However, if a force is now applied by the load to the output lever or output drive member, this force will act to swing the output drive member in one direction or the other about the pin 18 as a pivot and cause the locking element to be tilted as a result of the movement of pin 48, depending upon the direction of the force applied to the output drive member. The locking element will thus be fulcrumed about one or the other of the contact points 54a or 54b to bring the appropriate locking pin into gripped relation with the locking bar so as to positively hold the device in the desired position of adjustment.

With the locking element in a locked position, movement of the handle 32 or other connected actuating means to readjust the output member, will first act to move the locking element'to an unlocked position.

From the foregoing description and drawings, it will be clearly evident that the delineated objects and features of the invention will be accomplished.

Various modifications may suggest themselves to those skilled in the art without departing from the spirit of my invention and, hence, I do not wish to be restricted to the specific forms shown or uses mentioned, except to the extent indicated.

1 claim: 1. An irreversible locking control device, comprising:

a. an elongate locking bar;

b. a structure normally movable on said bar in opposite directions under an applied input force, said structure having an output force transmitting member;

0. means for locking said structure against movement along said bar in response to a reversal of said output force, and also automatically releasing said structure for movement along said bar, said means including:

a tiltably mounted locking element,

means on said element positioned on one side of said locking bar and having a contact normally slidable on said bar during said normal movement of said structure and forming a fulcrum for tilting movement of the locking element in response to said reversal of said output force, and

contact means on said locking element positioned on an opposite side of said locking bar normally disengaged from said locking bar during said normal movement of said structure, said contact and said contact means coacting in response to said tilting movement of the locking element about said fulcrum to lockingly grip the locking bar.

2. A device according to claim 1, in which the locking element is connected at one end with said output member, said output member being movable to tilt said locking element in opposite directions, and in which the normally slidable contact comprises a pair of spaced contacts, and said contact means comprises a pair of spaced contacts in disengaged relation to the locking bar, whereby upon tilting movement of the locking element in each of its opposite directions, a contact in said one side of the locking bar and a contact in the opposite side of the bar will coact to grip the bar.

3. A device according to claim 2, in which a movable input member includes means for moving the locking element, when its contacts are in non-gripped relation with the bar, together with the output member as a unit to adjust the position of the output member in response to movements of the input member 4. A device according to claim 3, wherein the output member is supported for pivotal movement in opposite directions.

5. A device according to claim 1, wherein the locking bar is of arcuate configuration.

6. A device according to claim 5, in which the means on said element positioned on said one side comprises a wall portion with a-slot in which side portions thereof form spaced apart contacts for selective coaction with said contact means.

7. A device according to claim 5, in which the locking element is swingably connected at its inner end with a pivoted output member for tilting movements thereby in opposite directions, and in which the normally slidable contact comprises a pair of spaced contacts at an outer end portion of the locking element and said contact means comprises a pair of spaced contacts in disengaged relation to the locking bar, whereby a contact on said one side of the locking bar and a contact on the opposite side of the bar will coact to grip the bar as the locking element is swung in each of its opposite directions of movement by the pivoted output member.

8. A device according to claim 7, including means resiliently urging the locking element in a direction normally tending to maintain the normally slidable spaced contacts in engagement with the locking bar.

9. A device according to claim 1, including an input member and friction shoes carried by said locking element positioned on opposite sides of said locking bar, and spring means urging said shoes into engagement with said bar.

10. A device according to claim 9, wherein said spring means comprises a U-shaped spring member carried by said input member and having portions positioned on opposite sides of said locking bar, respectively engaged with said friction shoes.

11. A device according to claim 10, wherein the spring member provides a protective shield around the adjacent portions of the locking member and the locking bar. I

12. A device according to claim 9, wherein the locking bar has an opening defining an operational dwell position, and one of said friction shoes has a portion adapted to releasably seat in said opening at said dwell position.

13. A device according to claim 1, including an input drive member coupled with an output drive member, said drive members being pivoted on a common axis, said locking element having a connection with said output drive member, and an input actuating handle member selectively connectible with said input drive member in longitudinally reversed ositions.

4. A device according to claim 3, including an output lever having a head portion, and means for variably connecting said head portion to said output drive member whereby the angular position of said output lever may be varied throughout 360.

15. An irreversible locking control device comprising:

a. an elongate locking bar;

b. a structure normally adjustably movable on said bar in opposite directions under an applied input force, said structure having an output force transmitting connection and including a locking element supported for tilting movement from a normal non-locking position to a locking position in response to a reversal of said output force; and

c. bar contacting means carried by said locking ele ment operative in its non-locking position to permit said adjusting movements of the structure, and in the locking position of the locking element being operative to grip the bar and oppose movement of the structure from an adjusted position by said reversal of said output force.

Claims

1. An irreversible locking control device, comprising: a. an elongate locking bar; b. a structure normally movable on said bar in opposite directions under an applied input force, said structure having an output force transmitting member; c. means for locking said structure against movement along said bar in response to a reversal of said output force, and also automatically releasing said structure for movement along said bar, said means including: a tiltably mounted locking element, means on said element positioned on one side of said locking bar and having a contact normally slidable on said bar during said normal movement of said structure and forming a fulcrum for tilting movement of the locking element in response to said reversal of said output foRce, and contact means on said locking element positioned on an opposite side of said locking bar normally disengaged from said locking bar during said normal movement of said structure, said contact and said contact means coacting in response to said tilting movement of the locking element about said fulcrum to lockingly grip the locking bar.

3. A device according to claim 2, in which a movable input member includes means for moving the locking element, when its contacts are in non-gripped relation with the bar, together with the output member as a unit to adjust the position of the output member in response to movements of the input member.

4. A device according to claim 3, wherein the output member is supported for pivotal movements in opposite directions.

6. A device according to claim 5, in which the means on said element positioned on said one side comprises a wall portion with a slot in which side portions thereof form spaced apart contacts for selective coaction with said contact means.

11. A device according to claim 10, wherein the spring member provides a protective shield around the adjacent portions of the locking member and the locking bar.

13. A device according to claim 1, including an input drive member coupled with an output drive member, said drive members being pivoted on a common axis, said locking element having a connection with said output drive member, and an input actuating handle member selectively connectible with said input drive member in longitudinally reversed positions.

14. A device according to claim 13, including an output lever having a head portion, and means for variably connecting said head portion to said output drive member whereby the angular position of said output lever may be varied throughout 360*.

15. An irreversible locking control device comprising: a. an elongate locking bar; b. a structure normally adjustably movable on said bar in opposite directions under an applied input force, said structure having an output force transmitting connection and including a locking element supported for tilting movement from a normal non-locking position to a locking position in response to a reversal of said output force; and c. bar contacting means carried by said locking element operative in its non-locking position to permit said adjusting movements of the structure, and in the locking position of the locking element being operative to grip the bar and oppose movement of the structure from an adjusted position by said reversal of said output force.