Title:
Latch hook
United States Patent 3893603
Abstract:
A latch hook having a shaft with a blunted forward tip and opposed front and rear hooks. A latch pin is pivoted on the shaft and movable between engagement with the hook ends to selectively close one of the hooks, and a stop is mounted on the shaft rearwardly of the hooks to receive string carried thereover.
US Patent References:
Hook for mending runs
Semonsen - May 1925 - 1536274
Run mending needle
Messing - November 1931 - 1831872
/1848900.html
Messing - March 1932 - 1848900
Needle
De Spain - May 1936 - 2041674
Knitting needle latch
Page - July 1941 - 2249780
Hook for mending runs
Semonsen - May 1925 - 1536274
Run mending needle
Messing - November 1931 - 1831872
/1848900.html
Messing - March 1932 - 1848900
Needle
De Spain - May 1936 - 2041674
Knitting needle latch
Page - July 1941 - 2249780
Application Number:
05/464997
Publication Date:
07/08/1975
Filing Date:
04/26/1974
View Patent Images:
Export Citation:
Primary Class:
International Classes:
D04G3/02; D04G3/00; D05B85/00
Field of Search:
223/102,103,104 112/222,223,224 66/117,118,121
Primary Examiner:
Krizmanich, George H.
Attorney, Agent or Firm:
Jenkins, Hanley & Coffey
Claims:
I claim
1. A latch hook comprising: a shank having a first projection extending from near the forward end thereof generally rearwardly above the shank to form a rearwardly open first hook; a second projection on said shank spaced rearwardly from said first hook and extending generally forwardly above said shank to form a second hook in opposed relation with said first hook; and a latch pin pivotally mounted on said shank and movable about its pivot between engagement with the ends of said first and second projections to selectively close one of said first and second hooks.
2. A latch hook as set forth in claim 1 wherein said first projection is spaced a short distance rearwardly from the forward end of the shank, said shank forward end having a blunted, forwardly extending tip.
3. A latch hook as set forth in claim 1 with the addition extends generally a third projection on said shank extending generally upwardly therefrom and spaced rearwardly of said second projection, said third projection being for receiving and stopping string carried over said second hook and latch pin when said second hook is closed.
4. A latch hook as set forth in claim 2 wherein said shank extends linearly forwardly from its rearmost end, and is offset downwardly to the rear of said second projection and then curves generally forwardly and upwardly with said forwardly extending tip disposed below an imaginary centerline passing through the linear rear portion of said shank.
5. A latch hook as set forth in claim 2 wherein the forwardly extending tip of said shank and said first projection combine to form an upwardly open depression therebetween.
6. A latch hook comprising: a shank having a generally straight rear portion and a front portion downwardly offset from said rear portion, said front portion having a curved lower surface and a forwardly extending blunted tip; a first projection extending rearwardly above said shank from adjacent said forward tip to form a rearwardly open first hook; a second projection extending generally forwardly above said shank rearwardly of said first projection to form a forwardly open second hook in opposed relation with said first hook; a latch pin pivotally mounted on said shank between said first and second projections and movable about its pivot between engagement with the ends thereof to selectively close one of the first and second hooks; and a third projection extending generally upwardly from said shank adjacent said second projection to form a forwardly open stop for receiving and stopping string carried over said second hook and latch pin when said second hook is closed.
7. A latch hook as set forth in claim 6 wherein said forwardly open stop is disposed generally above said second hook.
1. A latch hook comprising: a shank having a first projection extending from near the forward end thereof generally rearwardly above the shank to form a rearwardly open first hook; a second projection on said shank spaced rearwardly from said first hook and extending generally forwardly above said shank to form a second hook in opposed relation with said first hook; and a latch pin pivotally mounted on said shank and movable about its pivot between engagement with the ends of said first and second projections to selectively close one of said first and second hooks.
2. A latch hook as set forth in claim 1 wherein said first projection is spaced a short distance rearwardly from the forward end of the shank, said shank forward end having a blunted, forwardly extending tip.
3. A latch hook as set forth in claim 1 with the addition extends generally a third projection on said shank extending generally upwardly therefrom and spaced rearwardly of said second projection, said third projection being for receiving and stopping string carried over said second hook and latch pin when said second hook is closed.
4. A latch hook as set forth in claim 2 wherein said shank extends linearly forwardly from its rearmost end, and is offset downwardly to the rear of said second projection and then curves generally forwardly and upwardly with said forwardly extending tip disposed below an imaginary centerline passing through the linear rear portion of said shank.
5. A latch hook as set forth in claim 2 wherein the forwardly extending tip of said shank and said first projection combine to form an upwardly open depression therebetween.
6. A latch hook comprising: a shank having a generally straight rear portion and a front portion downwardly offset from said rear portion, said front portion having a curved lower surface and a forwardly extending blunted tip; a first projection extending rearwardly above said shank from adjacent said forward tip to form a rearwardly open first hook; a second projection extending generally forwardly above said shank rearwardly of said first projection to form a forwardly open second hook in opposed relation with said first hook; a latch pin pivotally mounted on said shank between said first and second projections and movable about its pivot between engagement with the ends thereof to selectively close one of the first and second hooks; and a third projection extending generally upwardly from said shank adjacent said second projection to form a forwardly open stop for receiving and stopping string carried over said second hook and latch pin when said second hook is closed.
7. A latch hook as set forth in claim 6 wherein said forwardly open stop is disposed generally above said second hook.
Description:
BACKGROUND OF THE INVENTION
This invention relates to manually operated knitting implements, and more specifically, to an improved latch hook for use in making hooked rugs or the like.
A wide variety of so-called latch hooks or latch needles are available in the prior art, and these needles normally comprise a shank terminating at its forward end in a hook. A latch pin is pivotally mounted on the shank and movable between a closed position in engagement with the free end of the hook and an open position away from the hook free end. See for example U.S. Pat. Nos. 1,831,872 and 1,918,183.
In the past, latch needles have been most often used for pulling thread or the like through a closed thread loop to repair runs, ravels, etc., in knitted fabrics. Recently, however, these needles have been popular for use in making hooked rugs, which are fashioned by knotting precut lengths of yarn, usually wool, about a rug backing of cross-hatched canvas string, burlap, or the like. In making the rug, each knot is formed by looping a length of the yarn over the needle shank and by inserting the hooked end of the shank through the backing to engage a single backing string. By pushing forwardly on the needle, the backing string slides over the hook and shank to a position above the open latch pin, and the free ends of the yarn are then placed over the backing string within the open hook. By pulling rearwardly on the needle, the backing string swings the latch pin to a closed position to secure the free yarn ends within the hook. Upon further rearward motion, the yarn free ends slip out of the hook as they are pulled through the yarn loop to form the knot.
The use of conventional latch needles for making hooked rugs, however, has not been totally satisfactory because the operator is required to hold the yarn loop with one hand to keep said loop from slipping off the needle shank. The bulky hooked forward end of the needle is difficult to push through the rug backing to engage one of the strings, and no means are provided for indicating to the operator how far the needle should be pushed forwardly before the free yarn ends are placed within the hook. Moreover, the yarn loop is not carried to a position adjacent the rug string upon forward motion of the shank, and this requires that the loop be pulled adjacent the string as the yarn free ends are pulled through said loop if the knot is to be fully tightened. As a practical matter, the yarn free ends often pull out of the hook before the loop reaches a position adjacent the rug string, and this results in many loose knots which must be hand-tightened to thus make rug hooking a time-consuming procedure requiring an undesirable amount of close operator attention and manual dexterity.
In an attempt to solve some of the problems of conventional latch needles, some hooks have been proposed which essentially comprise a large needle having one pointed end with a closable eye at the opposite end. These needles are operated by stitching the yarn with a unidirectional motion through the rug backing so that tufts of the yarn extend upwardly therefrom to form the rug pile. For example, see U.S. Pat. No. 3,701,461. These needles, however, are considerably smaller in size than the conventional latch needles, and are therefore relatively difficult to handle. The yarn is not easily inserted within the closable needle eye, and several stitching motions are required to produce a single knot.
Therefore, it is desirable to provide an improved latch hook which controls the position of the yarn during operation with a minimum of manual assistance, and which is shaped to make engagement with a rug backing string fast and easy. Moreover, it is desirable to provide latch hook which reduces wasted motions, and which carries the yarn loop to a position where formation of a tight knot is assured.
SUMMARY OF THE INVENTION
In accordance with the invention, a latch hook is provided having a shank with a blunted pointed forward tip. A first hook extends upwardly from the shank adjacent said forward tip, and a second hook extends upwardly from the shank rearwardly of the first hook and in opposed relation therewith. A latch pin is pivotally mounted on the shank and is movable between engagement with the ends of said first and second hooks to close one of said hooks, and forwardly open stop means extend upwardly from the shank rearwardly of said hooks for receiving string carried over the shank.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention. In such drawings:
FIG. 1 is a side elevation of a latch hook embodying the invention;
FIG. 2 is an enlarged fragmentary top plan view of the latch hook of FIG. 1;
FIG. 3 is a perspective view of the latch hook in an initial stage of operation;
FIG. 4 is a perspective view of the latch hook in a subsequent stage of operation;
FIG. 5 is a perspective view of the latch hook in a still subsequent stage of operation;
FIG. 6 is a perspective view of the latch hook in a final stage of operation; and
FIG. 7 is an enlarged fragmented perspective view of a portion of the rug backing having lengths of yarn knotted thereon.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As illustrated in the drawings, a latch hook 10 of this invention generally comprises an elongated shank 12 formed from metal or a rigid plastic, or the like, having a front hook 14 and a rear hook 16. A latch pin 18 is pivotally mounted on the shank between the hooks, and is movable between engagement with the hook ends to close one of the hooks. Conveniently, the shank is rearwardly received in a conventional manner into a handle 20 which is shaped to comfortably fit the hand of a user.
As shown in FIGS. 1 and 2, the shank 12 is offset downwardly at 22 from the horizontal shank centerline a short distance from the front of the handle 20, and then extends generally forwardly with a continuously curving lower shank surface 24. The shank gradually narrows in width along its length from the rear toward the front, and then sharply narrows near the front, as at 27, before terminating at its forward end in a slightly upturned forward tip 26. Said tip 26 has a blunted forward end, and is disposed below the horizontal centerline of the handle for reasons which will hereafter become more apparent.
The front hook 14 is formed near the forward end of the shank by a projection 28 extending rearwardly from the forward tip 26 and spaced above the shank 12. The rear end of the projection 28 forms the free end of the front hook and has a generally rounded and blunted rear end to provide a smooth surface over which yarn, string, or the like will easily slide without snagging. Also, the projection 28 and the shank tip 26 combine to form an upwardly open depression 30 disposed therebetween.
The forwardly open rear hook 16 is spaced along the shank rearwardly of the front hook 14 and in opposed relation therewith. The free end of the rear hook 16 is formed by a second projection 32 extending forwardly from the shank offset portion and spaced above the shank. The projection 32 tapers inwardly along its length and terminates at its forward end in a blunted point. Another projection 34 extends upwardly and forwardly from the shank offset portion from a position above and behind the second projection 32. The projections 32 and 34 combine to form a forwardly open stop hook, or notch 36, located generally above the rear hook 16 and shaped for receiving and stopping string or the like carried over the upper surface of the shank.
The latch pin 18 is pivotally mounted by a rivet 40 on the shank 12 between the front and rear hooks 14 and 16. The pivot end of the latch pin is received in a longitudinally extending central slot 42 in the shank, and the shank is provided with a raised upper cam surface 45 extending along each side of the slot to assure that string or yarn slides easily over the shank 12 without catching or snagging. The length of the pin 18 is sufficient to engage and slightly overlie either the rear end of the front projection 28 to close the front hook 14, or the forward end of the rear projection 32 to close the rear hook 16. The free end 46 of the latch pin is flattened to assure that the pin is wider than the ends of either of the projections 28 or 32 to prevent yarn or string guided over the latch pin from catching on the projections. Moreover, the forward side of the pin end 46 has a circularly-shaped recess 48 shaped to matingly receive the rounded rear end of the projection 28 of the front hook 14.
A latch hook of this invention is particularly adapted for use in making hooked rugs wherein precut lengths of yarn are knotted about a rug backing. Such a rug backing 50 is shown in FIG. 3, and comprises a network of interwoven canvas string or the like. The rug pile is formed by knotting a length of the yarn 52, shown about the latch hook 10 in FIG. 3, about one of the backing warp strings 54 between adjacent weft strings 56, or vice versa. The knotting procedure is repeated with subsequent lengths of yarn until a knot is formed about each warp string between each adjacent pair of weft strings over the entire surface of the backing 50.
With this invention, each knot is easily and quickly formed by laying a length of the yarn 52 within the rear hook 16 to form a loop 51, as shown in FIG. 3. A selected rug string 54 is easily engaged, or picked up, by inserting the forward tip 26 of the shank 12 underneath the rug string 54 and by pushing the latch hook forwardly, as shown by arrow 100. Such engagement of a rug string 54 with the shank forward tip 26 is fast and easy because the tip 26 is sharp enough to easily fit through the rug backing but is not so sharp as to catch or snag on said backing. Moreover, since the tip 26 is disposed below the horizontal centerline of the handle 20, the operator's fingers as well as the handle 20 are located above the rug backing and do not interfere with engagement of the rug string 54.
As the latch hook is pushed further forwardly, the string 54 rides over the tip 26 and slips downwardly within the depression 30 to permit the tip 26 to rise up on the opposite side of the string 54 to assure that only one rug string is engaged by the latch hook. The rug string 54 then rides up out of the depression 30 and over the projection 28 of the front hook 14. If the latch pin 18 is not already in a rearward position to close the rear hook 16 as shown in FIG. 3, the rug string 54 engages the free end 46 of the pin 18 and swings the pin to a rearward position to close the rear hook and secure the loop 51 therein. Upon further forward motion as shown in FIG. 4, the string 54 rides over the shank cam surface 45 and the latch pin 18, and is received and stopped in the notch 36 generally above the loop 51. The length of the latch pin is such that the rug string drops downwardly off the end 46 of the pin upon reception in the stop 36.
With the rug string 54 held in the stop 36, the free ends 53 of the yarn 52 are placed over the top of the string 54 generally within the front hook 14, as shown in FIGS. 4 and 5. The latch hook is then pulled rearwardly in the direction of arrow 102 in FIG. 5, to cause the rug string 54 to engage the end 46 of the latch pin 18 and pivot the pin to a forward position to close the front hook 14. The motion of the swinging latch pin assures that the yarn free ends 53 are carried into and secured within the front hook 14, and the rounded rear end of the projection 28 is matingly received in the latch pin recess 48 to help prevent snagging of the yarn on the projection 28. The rug string then rides over the shank cam surface 45 and the latch pin 18, and drops off the forward shank tip 26. As shown in FIG. 6, this rearward motion pulls the free yarn ends 53 through the yarn loop 51 to tightly knot the yarn about the rug string.
As shown in FIG. 7, each knot formed by the latch hook of this invention is identical. The free ends 53 of each length of yarn are tightly pulled through the looped portion 51 so that they extend upwardly from the rug backing 50 to form the rug pile. The knotting operation is repeated until a knot is formed about each rug warp string 54 between adjacent weft strings 53.
A latch hook of this invention is significantly faster and easier to use than those previously available. The pointed shank tip permits fast and accurate engagement of a single rug string. The length of yarn is looped about the shank in a specified position, and is held in such position by the latch pin. The yarn loop is carried to a position close to the rug string by the forward motion of the latch hook to assure that the knot will always be pulled tight before the yarn free ends slip out of the latch hook. Moreover, forward motion of the latch hook is stopped when the rug string is received in the notch to minimize wasted motion, and the latch pin is always carried to the proper front or rear position by the motion of rug string sliding thereover.
This invention relates to manually operated knitting implements, and more specifically, to an improved latch hook for use in making hooked rugs or the like.
A wide variety of so-called latch hooks or latch needles are available in the prior art, and these needles normally comprise a shank terminating at its forward end in a hook. A latch pin is pivotally mounted on the shank and movable between a closed position in engagement with the free end of the hook and an open position away from the hook free end. See for example U.S. Pat. Nos. 1,831,872 and 1,918,183.
In the past, latch needles have been most often used for pulling thread or the like through a closed thread loop to repair runs, ravels, etc., in knitted fabrics. Recently, however, these needles have been popular for use in making hooked rugs, which are fashioned by knotting precut lengths of yarn, usually wool, about a rug backing of cross-hatched canvas string, burlap, or the like. In making the rug, each knot is formed by looping a length of the yarn over the needle shank and by inserting the hooked end of the shank through the backing to engage a single backing string. By pushing forwardly on the needle, the backing string slides over the hook and shank to a position above the open latch pin, and the free ends of the yarn are then placed over the backing string within the open hook. By pulling rearwardly on the needle, the backing string swings the latch pin to a closed position to secure the free yarn ends within the hook. Upon further rearward motion, the yarn free ends slip out of the hook as they are pulled through the yarn loop to form the knot.
The use of conventional latch needles for making hooked rugs, however, has not been totally satisfactory because the operator is required to hold the yarn loop with one hand to keep said loop from slipping off the needle shank. The bulky hooked forward end of the needle is difficult to push through the rug backing to engage one of the strings, and no means are provided for indicating to the operator how far the needle should be pushed forwardly before the free yarn ends are placed within the hook. Moreover, the yarn loop is not carried to a position adjacent the rug string upon forward motion of the shank, and this requires that the loop be pulled adjacent the string as the yarn free ends are pulled through said loop if the knot is to be fully tightened. As a practical matter, the yarn free ends often pull out of the hook before the loop reaches a position adjacent the rug string, and this results in many loose knots which must be hand-tightened to thus make rug hooking a time-consuming procedure requiring an undesirable amount of close operator attention and manual dexterity.
In an attempt to solve some of the problems of conventional latch needles, some hooks have been proposed which essentially comprise a large needle having one pointed end with a closable eye at the opposite end. These needles are operated by stitching the yarn with a unidirectional motion through the rug backing so that tufts of the yarn extend upwardly therefrom to form the rug pile. For example, see U.S. Pat. No. 3,701,461. These needles, however, are considerably smaller in size than the conventional latch needles, and are therefore relatively difficult to handle. The yarn is not easily inserted within the closable needle eye, and several stitching motions are required to produce a single knot.
Therefore, it is desirable to provide an improved latch hook which controls the position of the yarn during operation with a minimum of manual assistance, and which is shaped to make engagement with a rug backing string fast and easy. Moreover, it is desirable to provide latch hook which reduces wasted motions, and which carries the yarn loop to a position where formation of a tight knot is assured.
SUMMARY OF THE INVENTION
In accordance with the invention, a latch hook is provided having a shank with a blunted pointed forward tip. A first hook extends upwardly from the shank adjacent said forward tip, and a second hook extends upwardly from the shank rearwardly of the first hook and in opposed relation therewith. A latch pin is pivotally mounted on the shank and is movable between engagement with the ends of said first and second hooks to close one of said hooks, and forwardly open stop means extend upwardly from the shank rearwardly of said hooks for receiving string carried over the shank.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention. In such drawings:
FIG. 1 is a side elevation of a latch hook embodying the invention;
FIG. 2 is an enlarged fragmentary top plan view of the latch hook of FIG. 1;
FIG. 3 is a perspective view of the latch hook in an initial stage of operation;
FIG. 4 is a perspective view of the latch hook in a subsequent stage of operation;
FIG. 5 is a perspective view of the latch hook in a still subsequent stage of operation;
FIG. 6 is a perspective view of the latch hook in a final stage of operation; and
FIG. 7 is an enlarged fragmented perspective view of a portion of the rug backing having lengths of yarn knotted thereon.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As illustrated in the drawings, a latch hook 10 of this invention generally comprises an elongated shank 12 formed from metal or a rigid plastic, or the like, having a front hook 14 and a rear hook 16. A latch pin 18 is pivotally mounted on the shank between the hooks, and is movable between engagement with the hook ends to close one of the hooks. Conveniently, the shank is rearwardly received in a conventional manner into a handle 20 which is shaped to comfortably fit the hand of a user.
As shown in FIGS. 1 and 2, the shank 12 is offset downwardly at 22 from the horizontal shank centerline a short distance from the front of the handle 20, and then extends generally forwardly with a continuously curving lower shank surface 24. The shank gradually narrows in width along its length from the rear toward the front, and then sharply narrows near the front, as at 27, before terminating at its forward end in a slightly upturned forward tip 26. Said tip 26 has a blunted forward end, and is disposed below the horizontal centerline of the handle for reasons which will hereafter become more apparent.
The front hook 14 is formed near the forward end of the shank by a projection 28 extending rearwardly from the forward tip 26 and spaced above the shank 12. The rear end of the projection 28 forms the free end of the front hook and has a generally rounded and blunted rear end to provide a smooth surface over which yarn, string, or the like will easily slide without snagging. Also, the projection 28 and the shank tip 26 combine to form an upwardly open depression 30 disposed therebetween.
The forwardly open rear hook 16 is spaced along the shank rearwardly of the front hook 14 and in opposed relation therewith. The free end of the rear hook 16 is formed by a second projection 32 extending forwardly from the shank offset portion and spaced above the shank. The projection 32 tapers inwardly along its length and terminates at its forward end in a blunted point. Another projection 34 extends upwardly and forwardly from the shank offset portion from a position above and behind the second projection 32. The projections 32 and 34 combine to form a forwardly open stop hook, or notch 36, located generally above the rear hook 16 and shaped for receiving and stopping string or the like carried over the upper surface of the shank.
The latch pin 18 is pivotally mounted by a rivet 40 on the shank 12 between the front and rear hooks 14 and 16. The pivot end of the latch pin is received in a longitudinally extending central slot 42 in the shank, and the shank is provided with a raised upper cam surface 45 extending along each side of the slot to assure that string or yarn slides easily over the shank 12 without catching or snagging. The length of the pin 18 is sufficient to engage and slightly overlie either the rear end of the front projection 28 to close the front hook 14, or the forward end of the rear projection 32 to close the rear hook 16. The free end 46 of the latch pin is flattened to assure that the pin is wider than the ends of either of the projections 28 or 32 to prevent yarn or string guided over the latch pin from catching on the projections. Moreover, the forward side of the pin end 46 has a circularly-shaped recess 48 shaped to matingly receive the rounded rear end of the projection 28 of the front hook 14.
A latch hook of this invention is particularly adapted for use in making hooked rugs wherein precut lengths of yarn are knotted about a rug backing. Such a rug backing 50 is shown in FIG. 3, and comprises a network of interwoven canvas string or the like. The rug pile is formed by knotting a length of the yarn 52, shown about the latch hook 10 in FIG. 3, about one of the backing warp strings 54 between adjacent weft strings 56, or vice versa. The knotting procedure is repeated with subsequent lengths of yarn until a knot is formed about each warp string between each adjacent pair of weft strings over the entire surface of the backing 50.
With this invention, each knot is easily and quickly formed by laying a length of the yarn 52 within the rear hook 16 to form a loop 51, as shown in FIG. 3. A selected rug string 54 is easily engaged, or picked up, by inserting the forward tip 26 of the shank 12 underneath the rug string 54 and by pushing the latch hook forwardly, as shown by arrow 100. Such engagement of a rug string 54 with the shank forward tip 26 is fast and easy because the tip 26 is sharp enough to easily fit through the rug backing but is not so sharp as to catch or snag on said backing. Moreover, since the tip 26 is disposed below the horizontal centerline of the handle 20, the operator's fingers as well as the handle 20 are located above the rug backing and do not interfere with engagement of the rug string 54.
As the latch hook is pushed further forwardly, the string 54 rides over the tip 26 and slips downwardly within the depression 30 to permit the tip 26 to rise up on the opposite side of the string 54 to assure that only one rug string is engaged by the latch hook. The rug string 54 then rides up out of the depression 30 and over the projection 28 of the front hook 14. If the latch pin 18 is not already in a rearward position to close the rear hook 16 as shown in FIG. 3, the rug string 54 engages the free end 46 of the pin 18 and swings the pin to a rearward position to close the rear hook and secure the loop 51 therein. Upon further forward motion as shown in FIG. 4, the string 54 rides over the shank cam surface 45 and the latch pin 18, and is received and stopped in the notch 36 generally above the loop 51. The length of the latch pin is such that the rug string drops downwardly off the end 46 of the pin upon reception in the stop 36.
With the rug string 54 held in the stop 36, the free ends 53 of the yarn 52 are placed over the top of the string 54 generally within the front hook 14, as shown in FIGS. 4 and 5. The latch hook is then pulled rearwardly in the direction of arrow 102 in FIG. 5, to cause the rug string 54 to engage the end 46 of the latch pin 18 and pivot the pin to a forward position to close the front hook 14. The motion of the swinging latch pin assures that the yarn free ends 53 are carried into and secured within the front hook 14, and the rounded rear end of the projection 28 is matingly received in the latch pin recess 48 to help prevent snagging of the yarn on the projection 28. The rug string then rides over the shank cam surface 45 and the latch pin 18, and drops off the forward shank tip 26. As shown in FIG. 6, this rearward motion pulls the free yarn ends 53 through the yarn loop 51 to tightly knot the yarn about the rug string.
As shown in FIG. 7, each knot formed by the latch hook of this invention is identical. The free ends 53 of each length of yarn are tightly pulled through the looped portion 51 so that they extend upwardly from the rug backing 50 to form the rug pile. The knotting operation is repeated until a knot is formed about each rug warp string 54 between adjacent weft strings 53.
A latch hook of this invention is significantly faster and easier to use than those previously available. The pointed shank tip permits fast and accurate engagement of a single rug string. The length of yarn is looped about the shank in a specified position, and is held in such position by the latch pin. The yarn loop is carried to a position close to the rug string by the forward motion of the latch hook to assure that the knot will always be pulled tight before the yarn free ends slip out of the latch hook. Moreover, forward motion of the latch hook is stopped when the rug string is received in the notch to minimize wasted motion, and the latch pin is always carried to the proper front or rear position by the motion of rug string sliding thereover.