US2204638A - Door opening mechanism - Google Patents

Description

June 18, 1940. w. F. WEATHERS 2,204,638

DOOR OPENING MECHANISM Filed May 10, 1937 ttornegs Patented June 18, 1940 UNITED STATES DOOR OPENING MECHANISM Warren F. Weathers, Detroit, Mich, assignor of one-half to Louis J. Flint, Detroit, Mich.

Application May 10, 1937, Serial No 141,597

2 Claims.

The present invention relates to apparatus for the conversion of rotary motion into rectilinear or straight line motion, or in other words, to apparatus for deriving rectilinear motion from a drive element which revolves, and although the apparatus is designed particularly for use as a door opener, it is also applicable to other types of mechanism and may insome instances be used in a reverse manner to secure rotary motion from a drive element having rectilinear motion.

The primary object of the present invention is to provide apparatus of the character above referred to embodying a plurality of rollers mounted in a carriage and supported thereby for engagement with a shaft or similar drive element, the axes of the plurality of rollers being disposed at an angle relative to the axis ofthe shaft or drive element whereby their frictional contact therewith causes rectilinear motion of the carria'ge upon the rotation of drive element.

Another object of the present invention is to provide apparatus of the character above referred to wherein the carriage is provided with resilient means for holding the rollers in frictional contact with the rotating drive element. The resilient support for the rollers provides for maintenance of a predetermined pressure upon the rollers and adapts the present apparatus for use with mechanism wherein it is desirable or essential that in the event of stoppage or opposition to the operation thereof, the means for providing rectilinear motion will not build up an excessive pressure on the mechanism being operated. For example, in door opening mechanisms it is desirable that in the event the door becomes stuck that the door opening mechanism should not exert sufficient pressure thereon to do damage to the door, the door opening mechanism itself or the means which connects the door opening 40 mechanism with the door.

' In the embodiment of the invention hereinafter described in detail the resilient means is made adjustable in nature so that the pressure on the rollers may be varied to suit loads of different types and weights, such as for example, doors of different weights and having different operating conditions.

Another object of the present invention is to provide apparatus of the character above referred to embodying at least three rollers spaced about a rotary drive element and mounted in a carriage with their axes angularly disposed and out of parallel with the axis of the drive element whereby each roller in contacting with the drive 55 element tends to hold the other rollers in contact with the drive element. A construction embodying at least three rollers is preferred for the reason that two rollers supported so that each tends to hold the other in contact with the drive element must be supported so that they engage 5 the drive element at diametrically opposite points and the carriage'must be guided by some supplemental means in order to maintain the rollers in the proper relationship with the drive element, especially in the case of a drive element having a small diameter. That is, the tendency for the rollers to become displaced laterally from the drive element is more pronounced in the case of a small diameter drive element and guide means must be provided to hold the carriage against lateral movement in order to hold the rollers diametrically opposite with respect to the drive element, and the friction caused by'engagement of the carriage with guiding means during its rectilinear motion results in a material power loss. An arrangement of three or more rollers eliminates the necessity for a carriage guide of this nature inasmuch as in grouping them around the drive element they maintain themselves in engagement with the drive element.

Another object of the present invention is to provide apparatus of the character above described with adjustable means whereby angularity of the rollers may be varied to cause variattion of the speed ratio between the rotary drive element and the element having rectilinear motion.

With the above and other ends in view the invention is more fully disclosed with reference to the accompanying drawing in which,

Figure 1 illustrates a door opening mechanism in elevation;

Fig. 2 is a side elevation of a motion converting unit;

Fig. 3 is an end elevation thereof;

Fig. 4 is a top plan view thereof;

Fig. 5 is a section of a roller;

Fig. 6 is an elevation partly in cross section illustrating a modified unit, and

Fig. '7 is an end view thereof partly in elevation and partly in cross section. 7

Like characters of reference are employed throughout to designate corresponding parts.

Referring to Figure 1 the numeral l designates a door such as is ordinarily used for garages and like buildings. The door has rollers 2 received in a guide track 3 and a link 4 attached to the upper end thereof whereby a horizontal force exerted upon the free end thereof will pull the door I upwardly and on to the horizontal poriii) tion 5 of its guides. The means for supplying a force upon the link 4 in order to raise or lower the door I in its guides comprises an electrical motor 6 connected to an elongate shaft 1 whereby operation of the motor causes rotation of the shaft. Control means for the motor 6 is generally designated at 8 and includes a switch 9 at each end thereof adapted when engaged by a traveler ID on the shaft 1 to open the motor circuit and stop rotation of the shaft 1. A second traveler H is mounted upon the shaft 1 and is connected to the link 4.

Each traveler comprises a carriage frame member l2 having a roller l3 mounted therein with its axis extending obliquely to the axis of the shaft 1, the roller preferably having an external portion I 4 formed of rubber or like resilient material whereby it is resiliently compressible. Pivoted at each end of the frame member I2 are swinging arms l5 and I6 having rollers l1 and I8 respectively, mounted therein with their axes angularly disposed with respect to the axis of the shaft 1. The arms l5 and I6 have projecting ears l9 thereon receiving a bolt 20 having a coiled spring 2| sleeved thereon and compressed between one of the ears I9 and a nut 22 on the end of the bolt. The spring 2| thus tends to draw the arms I5 and [6 together and the rollers supported thereby into engagement with the shaft 1, and engagement of the rollers I 1 and I8 with the shaft tends to draw the roller l3 into engagement with the shaft. The pressure of the spring 2| may be varied by adjustably moving. the nut 22.

Due to the angularity of the rollers l3, I1, and I8 with respect to the axis of the shaft 1 rotation of the shaft causes the carriage or traveler to move-in the direction of the length of the shaft; The speed'ratio between rotation of the shaft 1 and linear movement of the carriage or traveler is determined by the angularity of the roller axes and in the case of the traveler l0, where a comparatively short movement will suffice to actuate the switch 9, this angle is made comparatively small whereas in the case of the traveler II the angle is greater in order that the movement will be sufficient to completely open or close the door I.

In the case of traveler ll opposition to movement thereof tends to tip the traveler on the shaft and in order to prevent such tipping movement two units such as above described are united by a rigid plate 23 having an ear 24 thereon connected to the link 4, the link 4 in this case acting to prevent rotation of the traveler with the shaft 1.

Referring to Figs. 6 and 7 the numeral la designates a drive shaft having a plurality of rollers 25 grouped thereabout with their axes at an angle to the axis of the shaft 1a. A cylindrical body 26 has a rigid end wall 21 with bearings 28 therein receiving stub axles 29 on the rollers 25. A rotatably adjustable end wall 30 having a set screw 3| for holding it in positions of adjustment has bearings 32 therein receiving stub axles 33 on the other ends of the roller 25. A depending element 34 is provided on the cylindrical body 26 and is adapted to be connected by a link or other means to mechanism to be moved and such connection will act to prevent rotation of the cylindrical body 26 with the drive shaft 1a.

Due to the angularity of the rollers 25 and their contact with the shaft 1a rotation of the latter imparts rectilinear movement to the cylindrical body 26 providing the latter is held against rotation. The speed ratio between rotation of the shaft la and rectilinear movement of the cylindrical body 26 may be varied by varying the position of the end wall 30 with respect to the cylindrical body 26.

Although specific embodiments of the invention have been illustrated and described it will be understood that various changes may be made within the scope of the appended claims without departing from the spirit of the invention and such changes are contemplated.

What I claim is:

1. In apparatus of the character described, a

substantially cylindrical rotary drive element, at least three rollers grouped about said drive element for engagement with the outer periphery thereof and having their axes angularly disposed with respect to the axis of the drive element, a carriage carried solely by said rollers and movable axially relative to and upon rotation of said drive element, movable means holding said carriage against rotation, and means for varying the angularity of said rollers.

2. In apparatus of the character described having a drive shaft, a traveler device driven by and movable axially of the shaft comprisng a carriage having a pair of pivoted arms arranged to pivot toward and away from each other, a roller for engaging the periphery of the drive shaft and attached to said carriage, a pair of rollers carried one by each of said pivoted arms for engaging the outer periphery of the drive shaft, said first-named rollers and said pair of rollers being the sole support of said traveler device and having their axes of rotation angularly disposed relative to the axis of the drive shaft, spring means carried by said carriage and urging said pair of arms toward each other, movable with and holding said carriage against rotation.

WARREN F. WEATHERSi and means

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