US3106743A

US3106743A - Door closer assembly

Info

Publication number: US3106743A
Application number: US23458A
Authority: US
Inventors: David H Ellis; Elmer H Guse
Original assignee: OSCAR C RIXSON CO
Current assignee: OSCAR C RIXSON CO
Priority date: 1960-04-20
Filing date: 1960-04-20
Publication date: 1963-10-15
Anticipated expiration: 1980-10-15
Also published as: BE602829A; GB903664A

Abstract

903,664. Door closers. RIXSON CO., OSCAR C. April 20, 1961 [April 20, 1960], No. 14288/61. Class 65 (1). In a door closer having a door carrying spindle 3 (Figs. 5, 6) rotatably supported vertically in a casing 1 and a torsion-spring 31 secured at one end to the casing and pivotally connected at the other end to one end of a linkage 39, 41 pivoted in turn to a crank-plate 43 carried by the spindle, the outer edge of the crank-plate forms a cam surface having a stop 51 which is engaged by a spring- biased pivoted follower arm to hold the door in its open position. Means are also provided for selectively holding the follower arm in an inoperative position out of contact with the cam surface. The follower arm comprises a pair of arms 67, 69 (Figs. 12, 13) pivoted at 65 on either side of two symmetrical baseplates 57, 59 secured to the casing 1, a cam follower roller 72 being pivoted on a pin 71 between the extremities of the arms. A bar 81 which has an aperture 98 pivotally engaged with lugs 95, 97 on the arms, is slidably guided between a pair of ears 77, 79 extending from the plates 57, 59 by a pin 82 passing through a slot 99 and carries the springs 89, 91 which bias the arms and which act, respectively, between the arms and the ears and between an enlarged central portion of the bar and supporting brackets 73, 75 on the plates. The bar 81 and the arms 67, 69 are rendered free to follow the cam surface or are retracted therefrom by an eccentric selector cam 111 which is rotatably mounted in apertures 105, 107 in the ears 77, 79 and engages in an aperture 103 in the bar. The cam is rotated by turning a slotted head 113 (Fig. 5) recessed into the top of the casing and connected to the cam by an hexagonal shaft 112. The extent to which the door can open is limited by the engagement of the stop 51 with abutment surfaces 58, 60 on the plates 57, 59. In a modification (Fig. 15) the follower arm comprises a bell-crank 179 loaded by concentric springs 184, 185 and rendered inoperative by a selector crank 190 turned by a rod 191. Damping mechanism.-The damping mechanism comprises a cylinder block 116 (Figs. 4, 8a, 9) having cylinder bores 119, 121 of different sizes containing pistons 123, 125 pivotally connected by arms 127, 129 to opposite sides of a crank-plate 117 carried by the spindle 3 so that the pistons move in opposite directions when the door is opened or closed. During the opening movement of the door the smaller piston 125 moves towards the closed end of the cylinder 121 and the hydraulic fluid is expelled from the cylinder through a tapering V-shaped slot 146 in the cylinder wall, which extends from the open end of the cylinder for about three-quarters of the cylinder length, and through a passage 147 in the closed end of the cylinder which is controlled by an adjustable needle valve 148. The smaller piston consequently provides a damping action which increases as the door approaches its fully open position. When the door begins to close the piston 123 begins to move towards the closed end of the cylinder 119 and the hydraulic fluid, which entered the cylinder through a non-return valve 151 in the piston during the opening stroke, is expelled through a passage 152 in the cylinder wall controlled by an adjustable needle valve 155. When the door reaches a point about 15 degrees from its fully closed position the forward end of the piston 123 covers the passage 152 and its rearward end uncovers a passage 159 (Fig. 8a) which, together with passages 157 and 158 controlled by an adjustable needle valve 160, forms a by-pass to the piston. The speed of the final or latching portion of the door closing movement can thus be controlled independently by the valve 160. During the closing of the door hydraulic fluid flows into the cylinder 121 through a non-return valve 141 in the cylinder wall.

Description

Oct. 15, 1963 D. H. ELLIS ETAL 3,105,743

DOOR CLOSER ASSEMBLY Filed April 20. 1960 6 Sheets-Sheet 1 Oct. 15, 1963 D. H. ELLIS ETAL 3,1 ,7 3

DOOR CLOSER ASSEMBLY Filed April 20, 1960 6 Sheets-Sheet 2 k7 29? I a I i/ 69 63 \93 4 3VJNVENT0RS: fzzer/ z g'ase M K zI-Q-ur- Oct. 15, 1963 D. H. ELLIS ETAL DOOR CLOSER ASSEMBLY 6 Sheets-Sheet 5 Filed April 20, 1960 a 5; a 41- m 4 y 4 J i 9 bw 9 9 5 J 8 T Mi a m I J 06. 4% l. 5 W M: .9 w fi /r .7 v. 6 H l h 6% WV INVENTORS. zavzai/gmg (94467- 24 29x58 Oct. 15, 1963 D. H. ELLIS ETAL DOOR CLOSER ASSEMBLY 6 Sheets-Sheet 4 Filed April 20, 1960 :WMF

Oct. 15, 1963 D. H. ELLIS ETAL DOOR CLOSER ASSEMBLY Filed April 20, 1960 6 Sheets-Sheet 5 INVENTORS. fiavzdfi' ffvla 5 eQ/ JZJ' Q Oct. 15, 1963 D. H. ELLIS ETAL DOOR CLOSER ASSEMBLY 6 Sheets-Sheet 6 Filed April 20, 1960 a w e M W x 5 M M 6 .1 7 6 w g 4 w 5W U 3 6 7 1 W39 0/0 3:, g f v w- 0 w J %.NIM| w 5 4 Z 4 \1- O J, F), 3 w w b u NU. W w M/ 2 WW w 7., G II a. Z 1 H I Ally w United States Patent 3,106,743 DOOR CLOSER ASSEMBLY David H. Ellis, West Chicago, and Elmer H. Guse, Au-

rora, Ill., assignors to The Oscar C. Rixson Company, Franklin Park, Ill., a corporation of Illinois Filed Apr. Zil, 1960, Ser. No. 23,458 12 Claims. (Cl. 16-55) This invention relates to an improved door closer mechanism and more particularly to an improved spring actuated door closer mechanism including means for holding the door in the open position and for selectively rendering the hold open feature inoperative without limiting the angle of door swing.

Hold open devices of various types have long been recognized as desirable accoutrements for door closer devices generally. Originally, the primary function of a door closer was to return the door to the closed position automatically after it had been opened and released. However, after the initial development of the door closer or floor hinge, as it is often called, it became readily apparent that there was also need for a hold open device which could be used to hold the door in the opened position when that was desired. Particularly in the case of auditoriums and hospital rooms, for example, it was and is often desirable to retain the doors in the open position While large crowds are entering the auditorium or while a patient is being moved into or out of the hospital room. On the other hand, it is desirable in any case to have the door subjected to the operation of the closer during normal usage.

There have been numerous solutions to this problem which involve the use of devices extraneous to the closer itself to effect retention of the door in the open position. For example, one such solution utilizes an overhead guide rail including hold open means which functions at the end of door travel into the open position.

However, the trend in modern building construction has been toward the use of completely concealed door operating hardware. Not only does complete concealment present a highly desirable esthetic appearance, but also the utilization of a minimum number of exposed par-ts contributes to minimization of maintenance costs.

While the desirability of incorporating a hold open device in the door closer mechanism per se has been recognized, other demands upon the minimal space requirements of the closer mechanism made this extremely difficult. At the present time, door closer mechanisms not only serve to return the door to the closed position when released, but also include rather sophisticated dampening mechanisms to control the outward or opening movement of the door and also the closing movement of the door. As a refinement of these independent speed controls, a further refinement controls the latching speedof the door which is different from the stroke or closing speed of the door prior thereto.

Thus, the interior casings of door closer mechanisms find various functions competing for space which is critically limited by the requirements of most installations.

Therefore, it is not surprising that at the present time a number of hold open devices extraneous to the closer itself are being used nor that those door closers embody ing and including hold open means sacrifice the efiicient performance of the other functions. For example, many door closers utilizing hold open means either as an integral part or "as a separate assembly, render the hold open device inoperative only by limiting the angle of door swing. In other words, the terminal portion of the swing is used to engage the hold open device and when it is desired not to use the hold open device, the swing must be kept short to avoid it.

ice

Therefore, it is a primary object to this invention to provide a door closer assembly including improved hold open means mounted within the casing which will releasably retain the door in the open position, and which may be rendered inoperative without limiting the angle of door swing.

Further objects of this invention are to provide a simple and inexpensive hold-open sub-assembly for use with door closers of more or less conventional form and size which may be simply and easily inserted into the casing during assembly; which is sufiiciently small to be used with door closers including hydraulic dampening devices and without complicating the closer assembly or requiring increase in the casing size; which may be rendered operative or inoperative without breaking the casing seal; and which is rugged in construction and efiicient in operation. Still further objects are to improve the constructionof the conventional floor mounted closer and its operating components to enhance the efliciency of operation and to simplify its manufacture and assembly; to provide in such a device a positive stop means for limiting the maximum extent of door opening; and to embody in such a device a hydraulic back check and closing speed control without complicating the construction of the device or materially increasing its cost of manufacture.

A specific embodiment of the instant invention, together with a variation thereof, is shown in the accompanying drawings in which:

FIGURE 1 is a perspective view of the closer assembly, the position of the door being indicated by dotted lines;

FIG. 2 is a in FIG. 1;

FIG. 3 is a vertical sectional view of the door closer mechanism as taken substantially on line 33 of FIG. 2;

FIG. 4 is a horizontal sectional view of the closer shown in FIG. 3 taken substantially on line 44 in that figure;

FIG. 5 is a vertical sectional anism shown in FIG. 4 taken in that figure;

FIG. 6 is a horizontal plan view looking downwardly substantially from line 66 in FIG. 3 showing the hold open device in the operative position;

FIG. 7 corresponds to FIG. 6 except showing the hold open device in the retracted non-operative position;

FIG. 8 is a plan view of the twin cylinder dampening mechanism;

FIG. 8a is a fragmentary sectional elevational view of the closing stroke and latch valves and passages, as taken on line Sal-8a of FIG. 9;

FIG. 9 is an end elevational view of the twin cylinder dampening mechanism as viewed from the left of FIG. 8;

FIG. 10 is an enlarged vertical sectional view of a control valve to be used with the dampening means and taken substantially on the plane of line 10-10 in FIG. 9;

FIG. 11 is a perspective view of the hold open subassembly showing the assembly in the operative position;

FIG. 12 corresponds to FIG. 11 except showing the hold open sub-assembly in the retracted or inoperative position;

FIG. 13 is an exploded perspective view of the hold open sub-assembly showing the particular interrelation of elements;

FIG. 14 is a horizontal sectional view corresponding to that of FIG. 6 except showing another embodiment of the hold open sub-assembly in the operative position;

FIG. 15 is a view coresponding to FIG. 14 but showing the modified hold open sub-assembly in the retracted or non-operative position; and

FIG. 16 is an elevational view of the embodiment plan view of the closer assembly shown view of the closer mechsubstantially on line 55 shown in FIG. 14, but with the casing side wall broken away to show the internal components.

It is to be particularly noted that the door closer unit is comprised of a main casing 1, as best seen in FIG. 1, which fits into an outer casing, not shown, which is called the cement case. The outer casing is ordinarily recessed within a concrete floor beneath the door opening and when the main unit casing is installed therein only the spindle 3 projects above the floor, the top wall of the main casing being substantially flush with the finished floor surface.

Generally, the door closer assembly comprises a sealed casing 1 from which protrudes the spindle 3 carrying an arm 14% on which a door is mounted. The rotation of the spindle occasioned by the manual movement of the door to the open position serves to tension the energy storing spring 19 and is dampened by the twin cylindered dampening means 17. When the door is released the spring 19 normally returns the door to the closed position, the dampening means controlling the speed of the closing movement during both the stroke and latch portions of such movement.

More particularly, the inner housing or casing 1 comprises a bottom wall 4 and upwardly extending side walls 5 and 7 which taper in the horizontal direction from the end wall 9, adjacent the spring receiving portion of the casing, inwardly toward end wall 1 adjacent the spindle. The casing is further provided with an integral generally rectangular top wall 13 to which is secured a spring access opening cover 15. This casing is normally filled with hydraulic fluid.

The internal mechanism of the door closer is comprised generally of the spindle 3, a dampening mechanism 17, the coiled-spring energy storing device 19, and a hold open sub-assembly 21.

The spindle 3 extending through cover 13 is supported for rotation by a needle bearing assembly 23 located within the bearing housing 25 extending upwardly from the top wall 13. An 0 ring 27 surrounds the spindle 3 and provides a dirt seal preventing leakage of the hydraulic fluid upwardly along the spindle.

The lower end of the spindle is mounted for rotation on a ball thrust-bearing assembly 29 received within an annular recess in the bottom 4 of the casing 1.

The energy storing device 19 is mounted in the opposite end of the casing 1 and comprises a torsion spring 31 having its upper extremity extending radially inwardly to be engaged by a downwardly projecting portion of the spring access cover which may be rotated to tension the spring in a well known manner. The lower end of the spring 31 also terminates in a radially inwardly projecting portion which is engaged and supported by the car 33 of a spring carrier 35. The spring carrier 35 is mounted for rotation about spring post 45 the upper end of which is rotatably received within a cylindrical bore in a boss 46 integral on the spring access cover 15, and the lower end is secured within a bore the boss 47 formed integrally on the bottom 4 of the casing 1. The lower portion of the spring carrier 35 is supported axially by the upper surface of the boss 47.

The energy storing device 19 is actuated by means of a link assembly 37 (FIGS. 6 and 7) including two pivotally connected

arms

39 and 41, the opposite ends of the

link arms

39 and 41 being secured respectively to the crank plate 43 and the spring carrier 35. The link arm 39 is appropriately recessed, as at '40, adjacent the spindle 3 to permit greater angularity of spindle rotation. Thus, it will be seen from FIG. 6 that as the spindle 3 and crank plate 43 are rotated counterclockwise into the open position of the door the spring link assembly 37 tensions the torsion spring 31. When the door is released, the tensioned spring exerts a force on the link assembly 37 causing the crank plate 43 and spindle 3 to rotate clockwise into the closed position. This arrangement and operation of the spindle and the energy storing means 19 is well known in the door closer art.

The hold open aspect of the subject closer assembly is comprised very generally of the crank plate 43 aforementioned which is provided with a cam surface which interacts with the hold open sub-assembly 21 to prevent reverse rotation of the spindle 3 and hence the movement of the door to the closed position.

More particularly, the crank plate 43 is provided with a radially outwardly projecting angular cam and stop lug 51 which is the effective means used to hold the door in the open position because of its particular placement and relation to the hold open sub-assembly.

The bold open sub-assembly 21 is an integral unit which may be readily slipped into place within the main casing 1 during assembly operations, necessitating only the tightening of the screw 53 and the insertion of the guide pin 55 to hold it in proper operative position with respect to the aforementioned stop lug 51.

The hold open sub-assembly is best seen in FIGS. 11-13 in which the hold open assembly base structure is shown as comprised of two opposing generally symmetrical base plates 57 and 59. The body portions of the two base plates, indicated at 61 and 63 respectively, are provided at their forward ends with aligned apertures for receiving the pivot pin 65 which pivotally secures the two spaced and

parallel follower arms

67 and 69 disposed one on either side of the joined plates 57-59. The extremities of each of the

follower arms

67 and 69 are further provided with aligned apertures 70 for receiving pin 71 which rotatably supports a cam follower 72. This provides a reciprocable cam follower extending laterally and forwardly with respect to the forward ends of the base plates. Further the forward ends of the two base plate bodies 61-63 terminate in a pointed portion having an angularly disposed edge, 58 and 6t} respectively, facing in the direction of the crank plate stop lug 51 and providing a limit stop against which said lug 51 abuts to terminate the door opening rotational movement.

The tail ends of each of the base plates curve laterally to form

support brackets

73 and 75, each including a spring mounting stud 74. Each of the base plates 57 and 59 are further provided with laterally projecting ears 77 and 79, extending outwardly from the central portions of the plates, which are bent oppositely from the planes of the respective base plates to form a space therebetween for slidably receiving a cam follower bar 81. Cam follower bar 81 comprises a generally rectangular central body portion having two

spring mounting areas

83 and 85 extending longitudinally from respective opposite ends.

Helical compression springs 89 and 91 are threaded over the

arms

83 and 35 respectively, and when the follower bar 81 is mounted between the bars 77-79 of the base plates the spring 91 bears between the adjacent end of the follower bar body portion 81 and the brackets 73-75. The follower bar 81 is retained between the ears 77-79 by means of a guide pin S2, mounted in suitable aligned apertures in the ears 77-79, which passes through an elongate longitudinally extending slot 99 formed in the follower bar body and the follower bar is proportioned so that its end adjacent the brackets 73-75 normally projects beyond the rear edges of the ears 77-79. The spring 91 thus normally urges the follower bar in the leftward direction as seen in the drawings.

After the spring 89 is mounted on the arm 83 of the follower bar 81, a swing washer 93 is threaded over the end of the arm 83 and the end of the arm is then connected to the follower arms 67-69 by means of lugs 95-97 formed on the rear edges of the follower arms, which lugs project inwardly toward each other to engage in an aperture 98 in the arm 83. The swing washer 93 is a flat plate, centrally apertured to receive the end of the arm 83, which provides a seat for the adjacent end of the spring 89. Also, as shown, the swing washer 93 is provided with forwardly turned flanges on its upper and lower edges, which flanges overhang the external faces of the assembled follower arms 67-69 and keep them from spreading, under load, so as to disengage the lugs 95-97 from the aperture I93 in the follower bar 83.

The spring 89 bears between the swing plate 93 and the forward edges of the ears 77-79 and thus normally urges the follower arms 67-69 to the left as seen in the drawings. Since the follower arms are connected to the follower bar 81., by means of the arm '83, the spring 89 adds its eifect to that of spring 91.

To render the hold open sub-assembly operative or inoperative, the cam follower bar 81 is further provided with a generaly rectangular aperture 103 which is generally aligned with relatively large circular apertures 165 and 187 formed in the cars 77 and 79, respectively. The cam follower bar 81 and consequently the

cam follower arms

67 and 69 are rendered free to follow the movement of the cam surface or are retracted therefrom by an eccentric selector cam 1.11 which comprises a rotatable body extending through the respective apertures 105, 1G3 and 107. The eccentric selector cam functions to shift the cam follower bar 81 from left to right against the force of springs 89-91, as viewed in FIG. 13, and for holding bar '81 and the follower arms 67-69 in a retracted position wherein the cam roller 72 is retracted from position of engagement with the cam lug 51 of the crank plate 43. More particularly, the selector cam comprises an upper hexagonal nut portion 108 and axially spaced and aligned upper and lower cylindrical portions 109 respectively located to be rotatably engaged in the apertures 165 and 197 of the cars 77 and 79. The selector cam 1 11 is located eccentrically between the upper and lower cylindrical portions 1&9. As shown, the nut 108 is provided with an Allen type of hexagonal socket to receive an hexagonal shaft 1-12 extending downwardly from a slotted head 113 recessed into a suitable well opening to the top surface of the casing wall (FIG. 5).

When the nut MP8 is turned, by means of the shaft 112 and slotted head 113, to shift the cam 111 to the position shown in FIG. 6, the cam follower bar 81 is moved to the left under the action of the springs 89-91 and the hold open means is then in its operative condition wherein the follower roller 72 is in position to be engaged by the cam lug 51 on the crank plate 43 upon opening movement of the door mounted on the spindle 3. The hold open unit or assembly then appears as in FIG. 6. Under this condition and when the door approaches its terminal open position the stop lug 51 engages the follower roller '72, forcing it and the follower arms 67-69 to yield against the springs 89-91 sufficiently to allow the lug 51 to pass the roller 72. Opening movement of the door, turning the spindle 3 in the counterclockwise direction as seen in the drawings, then continues until the lug 51 engages the fixed limit stop means provided by the angularly disposed end edges 58-60 on the base plates 57-59 of the hold open unit. At this point the cam roller 72 is urged forwardly by the springs 89-91 to engage the crank plate 43 behind the ing 51 thereby retaining the crank plate against reversal of movement direction, under the action of the energy storage spring 31, and holding the spindle 3 and the door carried thereby in the opened position.

When it is desired to close the door, manual force applied to the door in the closing direction will drive the crank plate 43 in the clockwise direction, as seen in the drawings, forcing the lug 51 past the cam roller 72 which yields to the right against the springs 89-91. This yielding of the roller 72 is permitted by the rectangular opening 103 in the follower bar 81 which, as shown, is shaped to allow sufficient space or clearance from the cam 111 for the necessary extent of movement of the follower bar, cam follower arms and cam roller to permit the lug 51 to pass.

Turning the nut 108 clockwise, 180 from the position shown in FIGURE 6, to shift the cam 111 to the position shown in FIGURE 7, forces the cam follower bar 81 to shift to the right, as seen in the drawings, against the action of the springs 89-1, thereby pulling the follower roller 72 rearwardly out of the path of the lug 51 on the crank plate 43. Under this condition the hold open mechanism is inoperative and the spindle 3 is free to turn in either direction, counterclockwise upon opening of the door and clockwise for automatic closing of the door under the action of the torsion spring 31.

In the present improved hold open mechanism construction and arrangement, however, the hold open unit serves the continuously etfective function of providing a fixed, positive, internal limit stop means for the maximum swing of the door in the opening direction. That is, the angular end edges 58 of the base plates 57-59 provide a fixed abutment for the crank plate lug 51 to limit counterclockwise rotation of the spindle 3, as shown in FIG. 7. This, of course, results in a very heavy load or force tending to displace the hold open unit from its mounted position within the main closer casing and, in order to withstand such force or shock, the hold open unit is supported by a relatively large pin or post 114 fixed in and projecting upwardly from the bottom wall 4 of the casing, as shown in FIG. 3. The base plates 57- 59 of the hold open unit assembly are provided with aligned apertures 115, as shown in FIGS. 11, 12 and 13, to receive this post 114, when the hold open unit is positioned within the casing during assembly of the closer mechanism and the post 114 functions along with the mounting screw 53 and the pin 55 to fix the hold open unit in the proper location with respect to the crank plate 43, the principal function of the pin 55 being to prevent rotation of the hold open unit about the mounting screw 53 when the unit is subject to the shock of stopping the swinging door movement.

The door opening back-check and door closing stroke and latch control mechanism of the improved door closer is comprised generally of a double cylinder block 116, and a pair of pistons which are appropriately actuated by a second crank plate 117 drivingly mounted on the spindle 3 above the main crank plate 43. As best seen in FIG. 4, the double cylinder block 116 is provided with two cylinder bores 119 and 121, of different sizes, each having a closed end and an open end, in which are received the correspondingly

sized piston

123 and 125, respectively. These pistons are pivotally secured on opposing sides of the crank plate 117 by means of curved connecting

arms

127 and 129 secured thereto by

pins

131 and 133, respectively, the opposite end of said arms being pivotally connected to the respective pistons by

pins

135 and 137.

As viewed in FIG. 4, the crank plate 117 is turned in the counterclockwise direction when the door is open, and in the clockwise direction when the door is closed. Thus, in the closed position indicated in FIG. 4, the larger piston 123 is completely within the cylinder bore 11% adjacent the closed end thereof, while the piston is at the open end of the cylinder bore 121. Upon opening of the door the positions of the

pistons

123 and 125 become reversed, and of course, when the door closes the pistons resume the position shown in FIG. 4. It is by virtue of this movement of the

pistons

123 and 125 in their respective cylinders that the back-check for the opening movement of the door and speed control for the closing movement of the door are effected.

In the present invention such control is obtained by hydraulic means and it should be noted that, in use, the casing of the closer mechanism is substantially filled with hydraulic fluid which serves not only to lubricate the various moving parts but also for control of the piston movement within the double cylinder block 116 during operation of the door.

The details of the double cylinder block for effecting hydraulic control of the door movement are shown in s eaves FIGS. 8 to 10 inclusive, and from these figures it will be seen that the cylinder block is provided with ports and passages for controlling the flow of hydraulic fluid into and out of the cylinders during movement of the piston therein. As shown in FIG. 8, the

pistons

123 and 125 are shown in the same relation as in FIG. 4 for the closed position of the door, and in operation the space between the piston heads and the closed end of the cylinders will be filled with hydraulic fluid.

The smaller piston 125 provides the back-check control for the opening movement of the door, that is, the counterclockwise rotation of the spindle 3 as shown in the drawing. This back-check control of the door movement is to prevent its slamming at the terminal end of its opening movement, when the door is opened suddenly or very rapidly. The ports for the smaller cylinder to control the flow of hydraulic fluid into and out of the cylinder are arranged to become progressively effective, as movement dampening means, as the piston 125 moves from the forward end of the cylinder 121 to the rearward end thereof during opening movement of the door. Thus, as shown in F168. 8 and 9, the small cylinder 121 is provided with three separate fluid passages for fluid flow between the cylinder 121 and the exterior of the cylinder block.

The first of these passages is a fluid inlet passage 139, adjacent the closed end of the cylinder 121, through which the fluid from the casing can freely enter the cylinder 121 during reverse movement of the piston 125 toward the open end of the cylinder. This passage 139 thus functions only for intake of the hydraulic fluid to fill the cylinder 121, without resistance, as the piston 125 moves outwardly during movement of the door in the closing direction and is controlled by a bail check valve 141, which seats on the end of a screw having a central bore 145 for passage of fluid therethrough. The screw 143 is disposed adjacent the bottom of the cylinder 121, laterally offset from the passage 13?, as indicated in FIGS. 8 and 9, and the bore 145 opens directly into the casing well below the fluid level therein. The passage 139 is offset from the axis of the screw 143 so that there is no possibility of the passage 139 being blocked by the ball 141. Thus, there is a constant and ample supply of fluid to flow freely into the cylinder 121 upon outward movement of the piston 12:? and yet, upon any inward movement of the piston, the ball 141 instantly closes the bore 145 so that fluid can be expelled from the cylinder only by way of one or both of the remaining passages.

A second fluid flow passage is provided by a V-shaped slot 146 in the wall of the cylinder 121, which slot extends from open end of the cylinder inwardly for about three quarters of the length of the cylinder, the slot 146 being tapered from its greatest depth and width at the open end of the cylinder until it merges with the cylinder wall at the inner terminal end of the slot. Thus, as the piston 125 progresses inwardly into the cylinder 121 the tapered slot 146 gradually becomes closed by the piston until when the piston reaches the inner end of the slot, flow through the slot is closed off.

The third fluid flow passage for the cylinder 121 is a passage 147 which leads from the rearward or closed end of the cylinder to the exterior of the cylinder block and is controlled by an adjustable needle valve 14% as shown in FIG. 9, this passage 147 leads upwardly from the cylinder 121 to the top surface of the cylinder block 116 where it is counterbored with a tapered seat for reception of the needle valve. A branch passage 14-9 leads from above the seat for the needle valve outwardly through the end wall of the cylinder block to the exterior thereof. Thus fluid flow through the passages 147-449 may be adjustably controlled by the needle valve 143 to any extent desired.

It will now be seen that upon inward movement of the piston 125 into the cylinder 121, fluid is expelled from the cylinder through the two

passages

146 and 147 until the piston closes off the inner end of the V-shaped slot 146, at which time fluid is expelled from the cylinder through the passage 147 alone. Thus, at the terminal portion of the inward stroke movement of the piston 125, the rate of fluid flow from the cylinder 121 will be only that permitted by the passage 147 which is adjustably regulated by the needle valve 14-3. In this manner the resistance to flow of fluid from the cylinder 121, as the result inward movement of the piston 125, can be regulated to be substantially any desired back-check or dampening eliect on the rotation of the spindle 3 and the speed or rate of movement of the door at the terminal portion of its opening operation can be checked and cushioned to any extent that operating conditions may require.

During closing movement of the door, or clockwise rotation of the spindle 3, the piston 125 moves outward- 1y from the cylinder 121, and in doing so draws fluid freely from the closer easing into the cylinder 121 through the passage 139. Thus, any movement of the piston 125 in the outward direction, upon closing movement of the door, causes an immediate filling of the cylinder space with hydraulic fluid so that no matter when, or how often, movement of the door may be stopped, intermediate the full open or closed positions, and regardless of how the door may be moved back and forth in a partly opened position, a fully operating and constant back-check is available to cushion the door in the opening direction. The ball check 141 operates instantly to close the intake passage 145' when the piston moves inwardly and hence a full and constant supply of fluid in the cylinder is always available for back-check control.

As shown, the outward movement of the large piston 123, from its cylinder 119, during opening movement of the door, has no effect upon speed or rate of door movement, because of the passage 15G extending through the piston 123, from end to end, through which fluid can readily flow from the rear end of the piston to the head end thereof, and thence into the cylinder 119. The passage 156 is, however, controlled by a ball check valve 151 so that upon inward movement of the piston 123 into the cylinder 119 fluid flow through the passage 159 is shut 011.

The function of the piston 123 and its cylinder 119 is to control the speed of closing movement of the door under the action of the power storage spring 31, and hence the piston 123 functions for this purpose only during movement from the open end to the closed end of the cylinder 119 or from left to right as viewed in FIG. 8.

The first portion of the movement of the door in its swing from full open position toward closed position is generally called the stroke movement, and the object of the speed control is to regulate the stroke movement so that it will be at a substantially constant rate as may be desired, generally relatively slow as compared to the normal rate at which the door is opened. This stroke speed continues until the door reaches the point about 15 from the fully closed position at which point it is often preferable to release the door or increase its speed of movement so that it will have suflicient momentum to overcome the resistance of the strike plate and the latch engagement and permit the door to become fully closed to the latched position. Also, it is sometimes desirable that the final portion of door closing movement be at a slower speed than that of the stroke movement. In either case, this final movement of the door to its fully closed position is generally called the latch movement. Thus, to control the stroke speed and the latch speed, the cylinder 119 must have two passages for discharge of hydraulic fluid from the cylinder and each of these passages must be suitably controlled by adjustable valve means.

As shown in FIGS. 8, 8a, and 9, the large cylinder 119 is provided with an appropriately located outlet passage 152 which leads upwardly through the cylinder block body to the upper surface thereof where it is counterbored as at 153 to provide a conical seat 154 for a needle valve .155 (see FIG. As shown, an open branch passage 156 leads laterally from the counterbore 153 above the valve seat 154 for discharge of fluid to the exterior of the cylinder block and directly into the casing. The passages 152-156 and the needle valve 155 comprise the stroke control means and the passage 152 is located in the cylinder wall, adjacent the closed end of the cylinder, at such a point that when the piston 123 covers the passage 152, in the course of its inward movement into the cylinder 119, the door will have reached a point about from its fully closed position. Thus, by regulating the amount of opening of the passage 152 by means of the needle valve 155, the stroke speed of door closing movement can be regulated to be fast, slow, or any intermediate speed, as desired.

For latch-movement speed-control of the closing door a second fluid outlet passage 157 is provided at the inner end of the cylinder bore 119, which passage 157 communicates with a longitudinal passage 158 in the body of the cylinder block leading rearwardly from the closed end of the cylinder to a point rearwardly of the passage 152 Where it joins with a passage 159 leading into the cylinder 119, the object of the passage 157158159 being to bypass the piston 123 when it closes off the port 152. As shown in FIGS. 8a and 9, the passage 159 leads from the interior of the cylinder 119 to the top wall of the cylinder block where it is counterbored to receive a needle valve 160 for controlling the rate of fluid flow through the passages. As will be apparent from FIG. 8, no fluid will flow through the passages 157-453-159 until after the rear end of the piston 123 uncovers the passage 159. Thus, until this point of piston movement is reached fluid can be forced out of the cylinder .159 only through the passages 152156, which are under control of the needle valve 155. Upon opening of the passage 159 however, speed control is wholly by means of the valve 160.

As indicated in FIGS. 9 and 10, the valves 14%, 155, and 160 are mounted in the cover plate 13, onto the bottom side of which the cylinder block 116 is mounted (see FIG. 3) and the valves extend from the cover plate 13 into the respective counterbores in the cylinder block for controlling the respective passages therein. Thus, from a practical construction standpoint the location of the valve 160 must be such as not to interfere with the cylinder block mounting screws 16 1 (see FIGS. 2 and 3). The valve 160 may be located rearwardly of the valve 155 a distance less than the width of the piston 123, and in such case the piston Wall at the head end is provided with an inwardly extending V-shaped notch 162 (see FIG. 8) leading rearwardly from the cylinder head, a sufficient distance as to permit flow of fluid through the passage 152 at least until the rearward end of the piston 123 uncovers the passage 159. In this manner when the passage 152, for the stroke control valve, becomes fully closed by the piston 123, the passage 159 is opened and fluid from the passage 157 can readily bypass the piston 123 under control of the valve 160. Thus, the valve 161) can be adjusted so that the closing speed of the door, as controlled by the piston 123, can be increased or decreased, as may be desired, for the terminal portion of its closing stroke. Also, the groove or notch 162, in the piston head, serves to provide a smooth interchange from one speed to another and functions to prevent door bounce when the transfer is from fast to very slow.

The arrangement of the valve 160' is shown in FIG. 8a and the arrangement of the

valves

148 and 155 is shown in FIG. 10. It will be understood, however, that any suitable arrangement of needle valve means may be employed. In the arrangement of FIG. 10 the needle valve 155 which is mounted in the cover plate 13 must span an open space between the cover plate 13 and the cylinder block 116, and hence must be packed to prevent leakage of fluid around the needle valve and to the upper side of the cover plate 13. Therefore, as shown in FIG. 10 the threaded head 163 of the needle valve 155 is threadedly engaged with a packing nut 164 which is received within a threaded opening 165 in the cover plate 13, and a suitable packing material 166, surrounding the head 163 of the needle valve 155, is disposed below the packing nut 164 and firmly clamped against the upper surface of a shoulder 167 formed in the cover plate 13 at the bottom of the opening 165.

In the operation of our improved door closer mechanism, which as shown is a left hand closer, the apparatus functions as follows: First, when the door mounted upon the arm 14- is moved in an opening direction, counterclockwise as viewed in FIG. 1, the rotation of spindle 3 moves both the first and second crank

plates

43 and 117 in a counterclockwise direction also. This rotation of the upper crank plate 117 causes the piston arm 127 to move rearwardly, to the left, pulling the larger piston 123 with it and simultaneously causes the piston arm 129 to move forwardly pushing the smaller piston inwardly toward the closed end of the cylinder bore 111. As the larger piston 123 moves rearwardly, the space between the piston head and the end of the cylinder 119 is immediately filled with fluid from the casing by means of the one-way passage through the piston 123, as shown in FIGS. 4 and 8. Thus, there is no resistance to outward movement of the larger piston 123 during the opening movement of the door. However, as the smaller piston 125 moves forwardly, the fluid in the cylinder 121 is forced out of the cylinder through the passages 1 36 and 14 7 at a gradually decreasing rate until adacent the terminal end of the piston stroke the resistance to outward flow of the fluid is built up to a point where the door movement is braked or dampened according to the ad ustment of the valve 148. Thus the terminal end of the door opening movement is cushioned and slamming of the door is obviated. The valve 148 provides a full hydraulic control for the terminal opening movement of the door and may be adjusted readily for either soft or rapid back-check according to the conditions under which the door is to operate.

As the first crank plate 4-3 is rotated in a counterclockwise direction, the crank arms 39'-41 rotate the spring carrier 45 in the counterclockwise direction, the ear 33 engaging the spring 31 and winding it to place it under tension and to store energy for closing the door.

As the crank plate 43 continues rotating in the counterclockwise direction the cam stop lug 51 pushes the follower roller 72 from left to right as viewed in FIG. 6, and moves past the roller 72 into the position abutting the fixed limit stop 53. The springs 39-91 resiliently hold the roller in the position shown in FIG. 6 wedging the lug 51 against the stop 58 to resist movement of the lug 51 in the clockwise direction in response to the force exerted by the torsion spring 31. However, when torque substantially in excess of that provided by the torsion spring 31 is applied to the door, the cam stop lug 51 will be forced past the resiliently biased cam roller 72, and the closing spring 31 then takes over to return the door to the closed position by means of the spindle 3.

In the event it is wished to render the door hold-open mechanism inoperative, the adjustment screw 113 is rotated until the selector cam 111 is moved into the position shown in FIG. 7. This retracts the cam roller 72 completely out of all contact with the cam surface and lug 51 thereby permitting the door to be operated and returned to the closed position in the normal manner by the main closer spring 31.

During the return of the door to the closed position, the upper crank plate 117 is rotated in a clockwise direction resulting in the movement of the smaller piston 125 rearwardly toward the open end of the cylinder bore 121,

11 and the larger piston 123 moves forwardly toward the closed end of the cylinder bore 119.

As the larger piston 123 moves forwardly the passage 150 is immediately closed by the ball check valve 151, and the fluid ahead of the piston 123 is discharged through the passage 152 under the control of the needle valve 155. The valve 155 thus controls the rate of closing movement of the door so that it is at a predetermined, uniform rate until the piston 1Z3 closes the port 152 and opens the passage 159. At this point the fluid bypasses the piston 123 by -'way of the

passages

157, 158 and 159, normally at a different rate than the How permitted by the needle valve 155. The speed of closing movement of the door is thus under full control from full open to fully closed position and may be adjusted, in either or both the stroke and latch portions of the door movement, at the option of the user, to suit any conditions of installation and service that may ar1se.

In the modified form of hold-open mechanism shown in FIGS. 14, 15 and 16, the crank plate 43' is provided with a camming surface formed by an outwardly projecting lug 51 and terminating in an abrupt radial shoulder 51" for retention of the cam roller 72.. In this embodiment the cam follower comprises a pivoted bell crank 179 having a bifurcated arm providing spaced

parallel follower arms

67 and 69 between the free ends of which is mounted the cam roller 72', by means of the roller mounting pin 71. The pivoted bell crank 179 is rotatably secured on a rising boss 181, formed on the bottom floor 4 of the casing 1, by a cap pin 133. Two concentric compression springs 184 and 185, disposed one within the other, are mounted between the rearward edge of the follower arms 6769' and the upwardly extending brace 187 formed on the horizontal mounting bracket 189, which in turn is secured to the casing by screws 196. These springs are held in place by mounting studs 1% and 188 on the follower arms and the base 187 respectively, and function to urge the follower arms and the cam roller 72. forwardly toward the crank plate 43.

To render the modified hold-open device operative or inoperative, a selector crank 191i is drivingly mounted on control rod 191, the lower end of which is rotatably mounted within an aperture in the horizontal mounting bracket 139. The opposite end of the control rod 191 extends through the casing top 13, and terminates in an adjusting screw as shown in FIG. 5. Crank 190 carries a downwardly projecting selector camming pin 193 adapted to engage the arm 1% of the bell crank 179, to swing the bell crank about its axis 183.

When the selector crank 190 is rotated into the position shown in FIG. 14, it is seen that the camming pin 193 is retracted away from the arm 195 so that the compression springs can urge the bell crank in the counterclockwise direction to move the cam roller 72 into the path of the camming surface 51 on the crank plate 43. However, when the selector crank 19% is rotated into the position shown in FIG. 15, the camming pin 193 engages the arm 1% of the bell crank to turn it clockwise against the springs 184185, moving the cam roller 72 rearwardly and away from the path. of the stop lug 51 a sufficient distance to permit the crank plate 4-3 to rotate between the open and closed positions without interference from the hold-open mechanism.

In the operative position of the hold-open mechanism shown in FIG. 14, the bell crank 179 and follower roller 72' yield in the clockwise direction, against the springs 184-1135, to pass the cam lug 51' during the terminal portion of door opening rotation of the spindle 3, and immediately afterward the roller 72' is engaged behind the shoulder 51 and held by the springs 184-185 to prevent reverse movement of the crank plate 43' under the influence of the closer spring 31. When it is desired to close the door, manual force on the door in the closing direction will force the cam lug 51 past the 12 yieldable cam follower roller 72' and the crank plate 43 is then free to turn the spindle 3 and to swing the door to its fully closed position.

It will be seen from the foregoing that an improved door closer assembly has been provided which includes improved hold-open means mounted within the assembly casing, which will releasably hold the door in the open position and which may be rendered inoperative without hindering, limiting or in any way effecting the operation of the remaining elements of the assembly, or the angularity of door swing; which provides an improved construction of the conventional fioor mounted door closer, and arrangement of its operating components, to enhance the efficiency of its operation and to simplify its manufacture and assembly; which includes an improved positive stop means for limiting the maximum extent of door opening; which includes an improved adjustable hydraulic back-chcck and a closing speed control capable of any combination of stroke and latch speeds within the capacity of the driving spring which provides an improved control means which, as well as the hold-open means, may be regulated from the exterior of the casing without breaking the hydraulic seal and which does not complicate the construction of the door closer or materially increase the cost of its manufacture.

Although but two specific embodiments of this invention have been herein shown and described, it will be understood that numerous details of the constructions shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

We claim:

1. In a door closing mechanism, a casing having a base, a top wall, and side and end walls extending therebctween, a spindle rotatably supported vertically within said casing adjacent one of said end walls and extending through said top wall for controlling the opening and closing movement of a swinging door carried by the spindle, a crank plate drivingly carried by said spindle within said casing and having a peripheral edge forming a radial cam surface including an outwardly projecting stop lug, spring means pivotally secured to said crank plate for storing energy during the door-opening rotational movement of said spindle and for urging said spindle to rotate said door to the closed position when the door is released, a pair of flat elongated base plates secured together in juxtaposed face to face relation and horizontally mounted within said casing in the plane of said crank plate, said plates terminating in angula'ted forward edges extending into the path of said stop lug as the crank plate turns with the spindle and forming a rigid stop surface for abutting engagement by said lug to terminate the dooropening rotational movement of said spindle, a pair of vertically spaced and parallel follower arms pivotally mounted on and extending laterally from opposite faces of said base plates adjacent said forward edges, a cam follower roller mounted between the free ends of said arms, a pair of vertically spaced parallel ears each projecting laterally from one of said plates in the direction of said follower arms, each of said plates terminating rearwardly in a tail portion projecting in the direction of said ears and spaced from said ears longitudinally of the plates, a cam follower bar pivotally attached to the free ends of said follower arms and received for reciprocation between said ears, said follower bar having an enlarged body portion intermediate its ends providing a central guide plate disposed between said ears, a spring mounted axially on one end of said follower bar between said guide plate and said tail portions, a second srring mounted on the other end of said follower bar between said ears and said follower arms, said springs normally urging said follower bar and follower arms toward said cam surface for engagement of the roller therewith the crank plate rotates, said roller engaging behind said stop lug when the spindle is turned to the full open position of the door for preventing reverse rotation of said spindle in response to the first mentioned spring means, a selector rod mounted vertically within said casing for rotation by means accessible from the top of said casing, and an eccentric cnank pin adjacent the lower end of said selector rod, said ears and said enlarged body portion of the follower bar having aligned apertures for receiving the lower end of said selector rod and the crank pin respectively, whereby rotation of said selector rod and crank pin in one direction will shift said follower bar against the force of the springs thereon to retract said follower arms and withdraw the roller from the path of crank plate stop lug and rotation of said selector rod in the opposite direction will release the follower bar for actuation of the roller toward the periphery of said crank plate by means of the follower bar springs.

2. In a door closer mechanism, a casing having a bottom, a top, and side and end walls extending therebetween, a spindle rotatably supported within said casing and extending through said top for controlling the opening and closing movement of a swinging door carried on said spindle, a crank plate fixed to said spindle within said casing, the radial edge of said crank plate forming a cam surface of increasing radius terminating in a shoulder facing in the direction of spindle closing rotational movement, spring means connected to said crank plate for storing energy during the door opening rotational movement of said spindle and normally urging said spindle to return said door to the closed position when released, a lever pivotally secured to said casing to provide a cam follower arm movable angularly toward and away from said crank plate in the plane thereof, a cam roller rotatably mounted on said cam follower arm, a second spring means normally urging said arm to swing said roller into contact with said cam surface and for engagement behind said can sunface shoulder, and selector means including a rod rotatably mounted vertically within said casing and terminating at its upper end in an adjustment head accessible through the top of the casing, said selector rod carrying an eccentric carn member at its lower end, and means acting between said eccentric cam member and said follower arm for forcibly retracting said arm and shifting the roller thereon from the path of said crank plate cam surface and against the action of said second spring means when said rod is rotated in one direction, rotation of said rod in the opposite direction releasing the last named means to shift the cam roller into the path of said crank plate cam under the urgency of said second spring means.

3. In a door closer mechanism, a casing having a bottom, a top, and side and end walls extending therebetween, a spindle rotatably supported within said casing and extending through said cover for controlling the opening and closing movement of a swinging door carried on said spindle, a crank plate fixed to said spindle within said casing, the radial edge of said crank plate forming a cam surface of increasing radius terminating in a substantially radial inwardly extending shoulder facing in the direction of spindle closing rotational movement, spring means connected to said crank plate for storing energy during the door opening rotational movement of said spindle and normally urging said spindle to return said door to the closed position when released, a bell crank lever pivotally secured to said casing to provide a cam follower arm movable toward and away from said crank plate in the plane thereof, a cam roller rotatably mounted on said cam follower arm for engaging said cam surface, a second spring means normally urging said arm to swing said roller into contact with said cam surface and for engagement behind said shoulder, the second arm of said bell crank being at an angle to the cam follower arm, and selector means mounted in the casing and comprising a vertical rotatable rod terminating in an adjustment head accessible through the top of said casing and having an id eccentric cam member adjacent its lower end in the plane of said second bell crank arm for engagement therewith, whereby rotation of said selector rod will cause swinging movement of said bell crank to shift the roller on said follower arm into and out of the path of said crank plate cam surface.

4. In a door closer mechanism, a casing having top and bottom, and side and end walls extend-ing therebetween, a spindle rotatably mounted vertically within said casing adjacent one of said end walls for controlling the opening and closing movement of a swinging door carried thereby, a first crank plate drivingly carried by said spindle, a hydraulic dampening means mounted centrally within said casing for operation by said first crank plate for regulating the speed of rotation of said spindle in both door opening and door closing directions, a second crank plate drivingly carried on said spindle below said first crank plate, said second crank plate having a radial edge forming a cam surface of progressively increasing radius in the angular direction opposite to door opening rotation of the spindle and terminating in a radially projecting stop lug, a torsion spring mounted in the casing adjacent the other end wall, link means connecting said spring means to said second crank plate for storing energy during the door opening rotational movement of said spindle and for urging said spindle to rotate said door to the closed position when the door is released, and a spring-biased cam follower means secured pivotedly in said casing to swing horizontally parallel with the plane of said second crank plate and carrying a cam roller disposed to normally contact said cam surface and to engage behind said stop lug when the spindle has rotated to the full open position of the door to prevent reverse rotation of said spindle toward the door closed position in response to the said spring means, selector means including a rotatable rod mounted vertically in said casing and terminating in an adjustment head accessible from the top of said casing, said rod having an eccentric oam member adjacent its lower end, and means actuated by said eccentric cam member for shifting said cam follower means angularly to move said roller into and out of the path of the second crank plate cam surface.

5. In a door closer mechanism, a casing having a base, a top, and side and end walls extending therebetween, a spindle rotatably mounted vertically within said casing adjacent one of said end walls for controlling the opening and closing movement of a swinging door carried thereby, a crank plate drivingly carried on said spindle, said crank plate having a radial edge forming a cam surface of pro gressively increasing radius in the angular direction opposite to the door opening direction of rotation of the spindle, said cam surface terminating in an outwardly projecting stop lug, a torsion spring mounted in the casing adjacent the other end wall, link means connecting said torsion spring to said crank plate for storing energy during the door-opening rotational movement of said spindle and for urging said spindle to swing said door to the closed position when the door is released; a hold open means comprising a flat elongated plate means fixedly mounted horizontally adjacent the bottom of said casing, said plate means terminating in an angulated forward edge located in the path of said stop lug to provide a stop surface for engagement by said stop lug at a predetermined point in the rotational movement of said spindle in the do or-opening direction, a follower arm pivotally mounted on said plate means adjacent said edge and extending laterally therefrom, a cam follower mounted on said arm adjacent the free end thereof and in the same plane as said crank plate for engagement with said cam surface, a pair of vertically spaced ears extending laterally from said plate means between the ends thereof in the direction of said follower arm, said plate means terminating in a laterally projecting tail portion at the end opposite said stop surface and in longitudinally spaced alignment with said ears, a follower bar pivotally attached to the free end of said follower arm and received for sliding reciprocation aromas between said ears, said follower bar comprising two oppositely and longitudinally extending spring mounting arms and an enlarged central body portion having an aperture therein, a spring axially threaded on one of said mounting arms between said body portion and said tail portion, a second spring mounted on the other of said mounting arms between said ears and said follower arm, said springs normally urging said follower bar in the direction to force said cam follower into contact with said cam surface to follow the contour thereof as it rotates in the door-opening direction and to engage behind said stop lug to hold said crank plate and prevent reverse rotation of said spindle toward the door-closed position in response to the said torsion spring means; and a selector rod mounted vertically within said casing for rotation by an adjustment head accessible from the top of said casing, an eccentric c amming pin carried by said selector rod adjacent its lower end, aligned apertures in said ears for receiving the lower end of said selector rod, and said camming pin being received in the aperture of the body portion of said follower bar, whereby rotation of said selector rod in one direction will cause said camming pin to shift the follower bar against the action of the springs thereon and retract the follower arm to move the cam follower from the path of the crank plate stop ing, and rotation of said selector rod in the opposite direction will release the follower bar and permit engagement of the cam follower with the crank plate.

6. In a door closer mechanism, a casing having a base, a top, and side and end walls extending therebetween, a spindle rotatably mounted vertically within said casing adjacent one of said end walls for controlling the opening and closing movement of a swinging door carried thereby, a first crank plate drivingly carried by said spindle, a fiuid dampening means mounted centrally within said casing and on the top wall thereof for operation by said first crank plate to regulate the speed of rotation of said spindle during opening and closing movement of the door, a second crank plate drivingly carried on said spindle i elow said first crank plate, said second crank plate having a radial edge forming a cam surface of progressively increasing radius in the angular direction opposite the door opening direction of rotation of the spindle, said cam surface terminating in an outwardly projecting stop lug, a torsion spring mounted in the casing adjacent the other end wall, link means extending beneath said dampening means and connecting said torsion spring to said second crank plate for storing energy during the door-opening rotational movement of said spindle and for urging said spindle to swing said door to the closed position when the door is released; a hold open means comprising fiat elongated plate means fixedly mounted horizontally adjaccnt the bottom of said casing, said plate means terminating in an angulated forward edge located in the path of said stop lug to provide a stop surface for engagement by said stop lug at a predetermined point in the rotational movement of said spindle in the door-opening direction, a follower arm pivotally mounted on said plate means adjacent said forward edge and extending laterally therefrom, a cam follower mounted on said arm adjacent the free end thereof and disposed in the same plane as said second crank plate for engagement with said cam surface, a pair of vertically spaced ears extending laterally from said plate means between the ends thereof and in the general direction as said follower arm, said plate means terminating in a laterally projecting tail portion at the end opposite said stop surface, said tail portion being longitudinally spaced from said ears and extending in the same direction, a follower bar pivotally attached to the free end of said follower arm and received for sliding reciprocation between said ears, said follower bar comprising two oppositely and longitudinally extending spring mounting arms and an enlarged central body portion having an aperture therein, a spring axially threaded on one of said mounting arms between said body portion and said tail, a second spring mounted on the other of said mounting arms between said ears and said follower arm, said springs normally urging said follower bar in the direction to force said cam follower into contact with said can surface to follow the contour thereof as it rotates in the door-opening direction and to engage behind said stop lug to hold said crank plate and prevent reverse rotation of said spindle toward the door-closed position in response to the said torsion spring means; and a selector rod mounted vertically within said casing for rotation by an adjustment head accessible from the top of said casing, an eccentric camming pin carried by said selector rod adjacent its lower end, aligned apertures in said ears for receiving the lower end of said selector rod, said camming pin being received in the aperture of the body portion of said follower bar, whereby rotation of said selector rod in one direction will cause said camming pin to shift the follower bar against the action of the springs thereon and retract the follower arm and move the cam follower from the path of the crank plate stop plug, and rotation of said selector rod in the opposite direction will release the follower bar and permit engagement of the cam follower with the crank plate.

7. In a door controlling mechanism, a casing, a spindle rotatably mounted vertically within said casing adjacent one end thereof for controlling the opening and closing movement of a swinging door carried thereby, a first crank plate drivingy carried by said siindle centrally thereon, a hydraulic dampening means mounted centrally within said casing for operation by said first crank plate for regulating the speed of spindle rotation during opening and closing movement of the door, a second crank plate drivingly carried on said spindle, said second crank plate having a radial edge of progressively increasing radius in the angular direction opposite the door-opening direction of spindle rotation to form a cam, surface, said cam surface terminating in a radially projecting reverse motion stop lug, door closing means connected to said second crank plate for rotating said spindle to swing the door to the closed position, a cam follower arm pivotally mounted in the casing for swinging movement of the free end of said arm toward and away from the spindle axis, a cam roller mounted on the free end of said arm and disposed in the plane of the second crank plate for engagement with said cam surface, spring means normally urging the free end of said arm toward said spindle for holding said roller in resiliently yieldable contact with said cam surface, said roller engaging behind said reverse stop lug when the spindle is rotated into the full door-open position to prevent reverse rotation thereof in response to the said door closing means, and a selector means including a rotatable rod mounted vertically within said casing and terminating at its upper end in an adjustment head accessible from the top of said casing, an eccentric member carried by said rod and positioned for selectively moving said follower arm pivotally against the action of said spring means to swing said roller out of engagement with the cam surface of said crank plate, and means connected with said follower arm for coacting with said eccentric member to move said follower arm toward and away from said crank plate.

8. In a door closer mechanism having .a housing and a rotatable spindle in said housing for supporting a swinging door, a hold open means comprising a cam member fixed to said spindle and disposed within said housing, said cam member having a peripheral edge providing a cam surface of progressively increasing radius in the angular direction opposite the d rection of spindle rotation during door opening movement of the spindle and terminating in a radially projecting stop lug, a follower arm pivotcdly mounted in said casing for swinging movement of its free end toward and away from said earn surface, a cam roller mounted on the free end of said arm for normally contacting said cam surface and engaging behind said stop lug when said spindle is rotated a predetermined amount in the door opening direction, spring means for normally urging said follower arm toward said cam surface, and

shiftable selector means for pivotally swinging said fol-' lower arm against the force of said spring means and away from said cam surface to position said roller out of the path of said stop lug, said follower arm being mounted on a plate which extends into the path of said stop lug to provide a fixed abutment for engaging the stop lug upon a predetermined extent of rotation of said spindle in the door opening direction.

9. The hold open device of claim 8 wherein the base plate is an elongate member and the pivoted follower arm extends laterally from adjacent the forward end thereof which extends into the path of the stop lug, and wherein the base plate has a pair of superposed ears projecting laterally in the direction as said follower arm and spaced rearwardly therefrom, a follower bar having one end pivotedly connected to the free end of said follower arm is slidably received between said ears, said ears and follower bar have aligned openings therethrough, and the selector means is rotatably mounted in the openings of said ears, said selector means having an eccentric element extending through the opening in said follower bar to engage the rearward edge thereof, and said fol-lower bar opening being elongated toward said follower arm to permit unimpeded swing movement of the said arm under the action of said cam surface on said cam roller.

10. The hold open device of claim 9 wherein the spring means is a helical compression spring threaded on said follower bar and bearing between said follower arm and said ears.

11. In an automatic door closer, a hold open assembly comprising an elongated fiat base plate, a follower arm pivoted on said base plate adjacent one end thereof and extending laterally from one edge thereof, a tail portion at the other end of said base plate extending laterally from said one edge, a pair of parallel vertically spaced ears projecting from said one edge of the base plate intermediate said follower arm and tail portion and spaced from each of them longitudinally of the base plate, a follower bar having an enlarged body portion slidably received between said tears and having one end pivotedly connected to the free end of said follower arm, a helical compression spring threaded on said follower bar between said follower arm and said ears and bearing against each of them, a second helical compres sion spring on said follower bar bearing between said tail portion and the said body portion of the follower bar, said ears having aligned annular openings therein and said follower bar having an opening registering with the openings of said ears, and a rotatable selector means mounted in the openings of said ears and having an eccentric portion extending through the opening in the follower bar body, said eccentric portion engaging the rearward edge of the follower bar body opening and the opposite edge of said opening being spaced forwardly from the eccentric portion to permit movement of the follower in the rearward direction independently of said selector means.

12. In a door closer mechanism having a housing and a rotatable spindle in said housing for supporting a swinging door, a hold open means comprising a cam member fixed to said spindle and disposed within said housing, said cam member having a peripheral edge providing a cam surface of progressively increasing radius in the angular direction opposite the direction of spindle rotation during door opening movement of the spindle and terminating in a radially projecting stop lug, a bell crank pivotally mounted in said casing and having an arm positioned for swinging movement of its free end toward and away from said cam surface, a cam roller mounted on the free end of said arm for normally contacting said cam surface and engaging behind said stop lug when said spindle is rotated at predetermined amount in the door opening direction, spring means for normally urging said follower arm toward said cam surface, and shiftable selector means comprising a rotatable eccentric member positioned to engage the other arm of the bell crank and operable to pivot the bell crank so as to swing the said one arm away from the cam member and hold the cam roller out of the path of said stop lug.

References Cited in the file of this patent UNITED STATES PATENTS