US2635934A

US2635934A - Friction latch for extension tables

Info

Publication number: US2635934A
Application number: US306009A
Authority: US
Inventors: Zack W Mcconnell
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-08-23
Filing date: 1952-08-23
Publication date: 1953-04-21
Anticipated expiration: 1970-04-21

Description

April 21, 195s Z. W. MGCONNELL 2,635,934

FRICTION LATCH FOR EXTENSION TABLES Filed Aug. 23, 1952 Gttorneg Patented Apr. 21, 1953 UNITED STATES PATENT OFFICE Claims.

This invention relates to extension tables having relatively moveable sections and which refers more particularly to an improved latch for securing sections of the table against relative movement.

The principal object of the invention is to provide a friction latch consisting of an inverted substantially U-shaped bracket Whose legs are provided with lined apertures for the sliding reception of a rod having one end supported by a bracket aixed on the under side of one of the table sections adjacent the dividing line between the sections and opposite the U-shaped bracket which is attached on the under side of the companion table section. At least one of the legs of the U-shaped bracket is resilient to a certain degree and is disposed at an obtuse angle in relation to that portion of the bracket which is aflxed to the table section s0 that in its normal angular position, the rod extending through the aperture therein will be frictionally gripped and held against longitudinal movement until the leg is displaced toward a position perpendicular to the plane of the rod so that the latter may be released for free longitudinal movement to permit movement of the table sections.

Another object of the invention is to provide a latch consisting of the rod held at one end against other than rotative displacement and supported intermediate its ends by the bracket having depending legs, provided with apertures through which the rod is capable of sliding displacement and in which one of the legs of the bracket is disposed at an angle in relation to the rod and to the companion leg of the bracket to frictionally engage the rod and hold the same against longitudinal movement, together with means for changing the angular position of the rod engaging leg of the bracket to free the rod for longitudinal displacement in the U-shaped bracket.

With the foregoing objects in view, the invention has further reference to certain features of accomplishment which will become apparent as the description proceeds, taken in connection with the accompanying drawings wherein:

4 Figure 1 is a view of an extension table 4in longitudinal cross section.

Figure 2 is a fragmentary sectional View of a table top on a larger scale showing the manner in which the friction latch is attached to the under side of the table top sections and the manner in which the sections are displaced by the latch mechanism.

Figure 3 is a sectional view on a still larger scale taken o-n line 3-3 of Figure 2.

Figure 4 is a view on yet :a larger scale showing a modified form of the invention.

Figure 5 is a detailed perspective view of the friction element per se shown in Figure 4.

Figure 6 is a side elevational view of another modcation of the invention, and

Figure 7 is a View in transverse section taken on line 'I-l of Figure 6.

Continuing with a more detailed description of the drawing, reference is made primarily to Figure 1 in which reference numeral I0 denotes generally a conventional table having top sections I I and I2 which are moveable in relation to each other for the incorporation of extension leaves between the sections. To the undersides of the sections II and I2 are afxed relatively sliding rails I3 of conventional design for maintaining rigidity between the sections in any position to which they may be adjusted.

The present invention consists of an L-shaped bracket I4 which is secured by screws or other means I5 to the under side of the table section II adjacent the meeting point I6 of the table sections. In a corresponding position opposite the bracket I4, a substantially U-shaped bracket or friction latch Il is aflixed by screws or other means I8 to the under side of the companion table top section I2. One leg I9 of the friction latch I'I is perpendicular to the plane of the table section I2 while the companion leg 20 of the latch is disposed at an obtuse angle in relation to the table top section I2 and to the plane of a rod 2| which extends through apertures 22 in aligned relationship in the legs I9 and 20 of the latch Il.

It is to be noted that that portion of the latch I'I which is affixed to the under side of the table top section I2 is secured by the screws I8 nearer the perpendicular leg I9 and that the unsecured portion of the latch is curved slightly downwardly. By virture of this construction the angular leg 20 is possessed of greater resiliency than if that portion of the latch member I'I engaging the table top section I2 is secured at both ends. Accordingly. the greater frictional force is brought to bear by the leg 20 on the rod 2| to .hold the latter against longitudinal movement.

In order to release the rod 2| for free longitudinal displacement in the apertures of the legs I9 and 20 of the friction member I'I, the leg 20 is required to be moved toward a position perpendicular to the plane of the rod 2 I. To accomplish this, a second and smaller rod 23 is arranged above and parallel with the rod 2| and extends through apertures 24 in the legs I9 and 20 of the latch member Il. One end 25 of the rod 23 is bent slightly at a point spaced from its extremity in the manner shown in Figures 1 and 2 and at its opposite end there is provided a iinger loop 26 at right angles to the plane of the rod so that the rod 23 may be rotated 180 to cause the leg 20 of the latch member I? to be moved in the manner prescribed to relieve the rod 2l of frictional engagement by the leg 23 to permit the table top sections H and l2 to be moved in relation to each other.

The end of the rod 2i which extends through the bracket i4 is embraced by a short length of coil spring 21 and which spring is interposed between the depending leg of bracket i4 and a washer 23 which latter is held on the rod by an enlarged head 29 formed on the end of the latter. On the opposite side of the leg of the bracket i4 is a protuberance 33 formed on the rod 2i to limit the degree of movement of the rod in relation to the bracket i4, which movement is under the control of a spring 21 and is provided so that maximum irictional restriction may be obtained between the bracket i4 and latch l1 to hold the table sections il and i2 securely together.

Referring now to Figures 4 and 5, an L- shaped bracket 3l is secured by means of screws or other means 32 to the under side of a table section 33 adjacent the meeting point 34 between section 33 and the companion table section 35. Secured by screws 33 to the under side of the table section 35 adjacent the meeting point 34 is a latch member 31. This latch member is in two parts. a stationary part 33 has a depending leg 39 andwhose end opposite the leg 39 is bent in substantially U-shape at 49, the upstanding end of the stationary portion 38, forming the leg of the U-shaped portion of 40 being formed by spaced apart legs 4I between which is disposed a moveable part 42. The moveable part 42 has a tail portion 43 which lies on the base of the U-shaped portion 49 of the stationary part 33 and is held thereon for slight tilting displacement by means of a. screw 44 passing through apertures in the base of portion 40 of part 38 and an aperture in the portion 43 of part 42. The portion 43 is biased by a coil spring 45Y surrounding the screw 44 intermediate the portion 43 of part 42 and a nut 46 threaded on to the end screw 44. The part 42. has a leg 41 which is provided with, an aperture 48 in alignment with an aperture 49 in the leg 39. A rod 50 extends through the apertures 48 andV 49 and is held friotionally against longitudinal movement by the angular position of the leg 41, under pressure imposed by the coil spring 45. That portion of the stationary partA 38 between the upstanding legs 4i is bent downwardly to form a stop l against which the leg 41 of part 42 engages when it is moved towards the perpendicular position to relieve friction-al tension on the rod 50. This is accomplished manually by engaging the leg 41 with a finger to tiltl the part 42 against the resistance of spring 45, while the rod 59 is engaged by the loop 52 and moved longitudinally to correspondingly move the table top sections 33 and 35.

Embracing the innerv end of rod 59 is a coil spring 53, held in position by a washer 54 and a cotter key 55. A cotter key 53 is shaped through a transverse aperture in the rod 59 on the side of the bracket 3i opposite the side against which the spring 53 bears. This arrangement provides limited longitudinal displacement of rod 50 to obtain maximum ofv friction on the rod by the angular leg 41 of part 42 of the friction latch to hold the table sections ilrmly together.

Referring now to Figures 6 and 7 showing a further modified form of the invention an L- shaped bracket 51 is secured by means of screws 58 to the under side of a table top section 59 adjacent the meeting point 60 between the section 59 and a companion section BI'. Adjacent the meeting point 93 a friction latch 52 is secured to the under side of table section 6l by means of screws 53. The latch member 62 is substantially inverted U -shape and the portion 34 thereof which is secured to the table section 9i is free at one end and curved slightly downwardly to lend resiliency to the leg 65 which is disposed at an obtuse angle in relation to aV rod 6B which extends through the lined apertures in the leg 55 and the perpendicular leg 31 of the latch member 52. The angular relationship between leg 65 and the rod 59 imposes a frictional force on the rod 66 in one. position of the latter, due to the fact that the, rod 66 is attened longitudinally at diametrically

opposite points

68 and 69, as revealed in Figure 7.

The rody 66 has a depending loop 19 on itsv outer end which provides a handle for rotating and longitudinally moving the rod. When the

ilat sides

68 and 69 are disposed on a horizontal plane as shown in Figure 7, the rod 66 may be. freely moved to displace theA table sections 59 and 6i. However, when the handle 10 is moved or to a horizontal position to dispose the at sides 53 and 59 in a vertical planev the rod is frictionally engaged by the leg 65 of the latch member 62 and holds. the` table sections together or in adjusted positions by preventing longitudinal displacement of the rod 86.

On the inner end of the rod B6 is mounted a coil spring 1i which is held thereon by a. washer 12 and the enlarged head 13 of the rod. A cotter key 14 is extended through the rod on the side of the bracket 51 opposite the spring 1l. The spring 1ll provides for limited longitudinal movement of the rod to oppose maximum friction on the latter to hold the table sections firmly together.

It is understood that whileY the invention has been described as providing afriction latch for the moveable sections of an extension table. it is clearly evident that the invention may be used wherever such a friction latch may be applicable.

Manifestly,l the construction (and process) as,` shown and described is capable of. some modiiication and such modification as may be construed to fall within the scope and meaning, of the appended claims is alsd considered to be within the spirit and intent of the invention.

What is claimed is:

1. A friction latch for relatively moveable members comprising a rod in a plane parallel with said members and secured at one end to one of said members for limited longitudinal and rotative displacement, a substantially U-shaped bracket defining a friction latch member affixed to the other of said relatively moveable members having a legperpendicular to the plane of said Y rod and a companion leg disposed atan obtuse a plane perpendicular to said rodto relieve friction between said leg and/rod to releasethe latter for free longitudinal displacement to effect corresponding movement of said relatively moveable members.

2. A friction latch for a pair of members mounted for relative displacement, comprising a friction member of resilient material aixed adjacent one end to one of said moveable members and having a portion curved away from said one of said members and having one end turned at right angles to the plane of said one of said members, a second leg formed on the end of the curved portion of said latch member and disposed at an obtuse angle in relation to the plane of said one of said members, a bracket aflixed to the companion moveable member adjacent the meeting point between said members, a rod parallel with the plane of said members and having one end mounted in said bracket for limited longitudinal and oscillative displacement, said rod extending through aligned apertures in the legs of said friction member and held against longitudinal displacement by frictional engagement between said rod and the obtuse angled leg of said friction member and means for changing the annular position of said obtuse angled leg in relation Ito said rod to free said rod and said relatively moveable members for longitudinal movement.

3. In a friction latch for relatively moveable members, a bracket xed to one of said relatively moveable members, a friction member affixed to the other of said relatively moveable members, said friction member having one leg at right angles to the plane of said relatively moveable members and the companion leg disposed at an obtuse angle in relation to the plane of said relatively moveable members, said legs having aligned apertures, a rod extending through the apertures of said legs and journaled at one end in said bracket for oscillative and limited longitudinal displacement and held against longitudinal displacement by the annular relationship of said obtuse angled leg with said rod and means for displacing said obtuse angled leg towards a perpendicular plane withrespect to said rod to release the latter for free longitudinal displacement and to eiTect corresponding displacement between said relatively moveable members.

4. The structure of claim 3 in which the latch member is secured only adjacent one end to a relatively moveable member and curved away from said member to contribute resiliency to said opposite end of said friction member.

5. The structure of claim 3 in which the end of said rod journaled in` said bracket is embraced by a coil .sp-ring and held against longitudinal displacement to a degree permitted by said spring to impose maximum frictional restraint on said rod to hold the relatively moveable members in secure juxtaposition.

ZACK W. MCC'ONNELT...

References Cited in the iile of this patent UNITED STATES PATENTS Number Name Date 687,431 Kimball Nov. 26, 1901 737,039 Stone Aug. 25, 1903 774,046 Davis Nov.. 1, 1904 1,425,833 Bowers Aug. 15, 1922 1,508,190 Ledbetter Sept. 9, 1924 2,588,174 Spielberg Mar. 4, 1952