US2649118A

US2649118A - Loom picking motion

Info

Publication number: US2649118A
Application number: US126950A
Authority: US
Inventors: Heath Barrie
Original assignee: HOBOURN AERO COMPOSNENTS Ltd
Current assignee: HOBOURN AERO COMPOSNENTS Ltd
Priority date: 1949-08-15
Filing date: 1949-11-14
Publication date: 1953-08-18
Anticipated expiration: 1970-08-18

Description

Au 18, 1953 B. HEATH v 1 91 LOOM PICKING MOTION Filed Nov. 14. 1949 6 Sheets-Sheet 1 Inventor Barrie Heath By 84 wMaMrL Attorney Aug. 18, 1953 B. HEATH 2,649,118

LOOM PICKING MOTION Filed Nov. 14. 1949 6 Sheets-Sheet 2 Invenlor Barn 6 ai'k By E wMM/wm Attorney Aug. 18, 1953 Filed NOV. 14, 1949 6 Sheets-$heet 3 4 -57 a7 57 57 25 m J :2" i 24 5a 57 5a 23 I Z5 40 Inventor 35 \L9/ 2 Bun: Hem 7'16. 6. 1o 17 y m. Wit

Attorney Aug. 18, 1953 B. HEATH 2,649,113

LOOM PICKING MOTION Filed Nov. 14, 1949 6 Sheets-Sheet 4 ATTORNEYJ' Aug. 18, 1953 B. HEATH LOOM PICKING MOTION A TTORNE Y3 Aug. 18, 1953 B. HEATH 2,649,118

LOOM PICKING MOTION Filed Nov. 14, 1949 6 Sheets-Sheet 6 4 FIG. 9.

Inventor Bar n e H'e ik Attorney Patented Aug. 18, 1953 LOOM PICKING MOTION Barrie Heath, Bar'ming, near Maidstone, England, assignor to Hobourn Aero Components Limited, Strood, Rochester, England, a British company Application November 14, 1949, Serial No. 126,950 In Great Britain August 15, 1949' 8 Claims. 1

This invention relates to loom picking motions.

It is an object of this invention to provide an improved pneumatically-operated picking motion adapted for propelling a shuttle through the shed of a loom with appreciable reduction in noise and of shock, as compared with shuttles propelled at the same picking rate by known picking motions.

Another object of this invention is to provide an improved picking motion comprising two pneumatically-operated picking units mounted one at each end of the loom race, each unit incorporating improved check means for bringing an incoming shuttle to rest in contact or substantially in contact wtih a picker when a piston associated with said picker is at the outer end of its stroke.

A further object of the invention is to provide an improved loom picking motion in which an air cylinder housing the piston with which the picker is associated has ports for the admission of air under pressure to move the piston in the shuttle-propelling direction and to return said piston to the outer end of its stroke after the shuttle-propelling stroke and for providing a cushion of air to buffer the piston at the end of the shuttle-propelling stroke.

Another object of the invention is to provide, for use in combination with a picking unit as above-mentioned, improved valve means for controlling the admission to the cylinder at appropriate times of air under pressure and for regulating the rate of flow of air to the cylinder for returning the piston to the outstroke position after its shuttle-propelling movement.

A further object of the invention is to provide a picking unit as above-mentioned in which the piston, with which the picker is associated, is made of such a length in relation to certain air ports at the instroke end of the cylinder as to function as a sleeve valve for piston-buffering purposes.

The foregoing and other objects of the invention will be readily appreciated from the following description and the accompanying drawings which disclose a number of embodiments of the invention.

In the drawings,

Figure 1 is a diagrammatic front elevation of a loom provided with one form of pneumaticallyoperated picking motion according to this invention,

Figure 2 is a longitudinal sectional plan view through the air cylinder and associated parts of one of the picker units employed in the embodiment illustrated in Figure 1,

Figure 3 is a cross section on line III, III of Figure 2,

Figure 4- is a longitudinal sectional view through the rotary distributor of one of the 2 picker units employed in the embodiment illustrated in Figure 1,

Figure 5 is a cross section of line V, V "of Figure 4,

Figure 6 is a View similar to Figure 4, but showing the valve rotor in another position,

Figure 7 is a diagrammatic front elevation of a loom provided with another form of pneumatically-operated picking motion according to this invention,

Figure 8 is a longitudinal sectional View through the air cylinder and associated parts of one of the picker units employed in the embodiment illustrated in Figure '7,

Figure 9 is an enlarged View of buffer means, and

'Figure 10 is a view similar to Figure 6, but showing a modified form of rotary distributor valve.

In the embodiment of the invention illustrated in Figures 1 to 6 of the drawings, a slender cylinder I is mounted as an extension of an end of the race 2 of the loom sley 3, with the longitudinal axis of the cylinder in axial alignment with the line of traverse of a shuttle 4 as it moves across the race 2. The loom sley 3 is supported in known manner by a pair of sley swords and is rocked by any suitable means. Within the cylinder I is freely slidable a piston 5 (see Figure 2) having a piston rod 6 which eX+ tends out through a gland I in that end of the cylinder I which faces across the loom and on the projecting ends of the piston rod 6 a shuttle picker 9 is attached. The shuttle picker 9 is adapted to make direct contact with the shuttle and the piston 5 in its operative, that is, its s'hu't tle-propelling stroke moves in the same direction as that in which the shuttle 4 is to be propelled by the picker 9.

At a suitable distance in from the inner end of the cylinder I, that is, the end having the gland I for the projecting end 8 of piston rod 6, an air pipe-line It! is connected, which includes an automatic one-Way spring-biased valve II adapted to allow air to escape from but not enter the cylinder 5 through the port I2. On the outlet side of this automatic one-way valve II a by-pass or branch pipe I3 leads from the pipe-line II) to an inlet port I4 close to the inner end of the cylinder I. In this by-pass I3 are set a restrictor valve I5 of needle or other suitable adjustable orifice valve leading to a second automatic one-way spring-biased valve I 6 which allows air to enter but not escape from the cylinder I through the port I4. Air to efiect the up erative stroke of the piston 5 is introduced through a pipe-line I! connected to the outer end of the cylinder I: and the flow of air through this pipe-line I7 and through the pipe-line Hi, which includes the first-mentioned one-way valve the picker II, and to which the by-pass or branch pipe I3 is connected, is controlled by a, rotary distributor valve I8, shown in detail in Figures 4, 5 and 6.

Each rotary distributor valve I8 comprises a fixed housing I9 having a through bore 20, the open ends of which are closed by detachable covers 2|, 22 respectively. Within the housing bore is accommodated a cylindrical plug-like rotor 23 journalled on a spigot 24 in cover 22 and on a driven shaft 25 passing through cover 2|. The driven shaft 25 of the rotor 23 is adapted to be drivingly connected to a driving shaft 21 which is continuously rotating synchronously with the swinging loom sley. Such a shaft usually exists already in a loom of this type. The drive is effected by a pulley 26 on the rotor shaft 25, another pulley 28 on said shaft 21 and an endless belt 29. The wall of the housing 19 is provided with four ports 38, 3|, 32 and 33, port 30 being connected by a pipe-line 34 to a pressure air main 35, port 3| being connected to an exhaust tube 35, and

ports

32 and 33 being connected to pipe-lines I! and I0 leading to the outer and inner ends of cylinder I respectively. The peripheral surface of valve rotor 23 is provided with two sets of pockets, each set comprising four

pockets

31, 38, three pairs of which are cross-connected by three inclined passages 39. The

remaining end pockets

31, 38 are interconnected by a passage 40. A clearance is provided between the periphery of rotor 23 and the valve housing bore 28 and the rotor 23 is supported by a number of packing rings 4| which are arranged between the

pockets

31, 38, so that no appreciable amount of air can pass between adjacent surface pockets.

The admission of air under pressure, through pipe-line Il, under the controlling action of the distributor valve I 8, to the outer end of the cylinder I so as to act on the outer face of the piston 5 causes the piston 5 to move rapidly with the piston rod 6 and the shuttle picker 9. Air on the other, that is, inner side of the piston 5 is, at the same time, expelled through the first port I2 and the one-way valve II, until the piston 5 passes over port I2 leading to that one-way valve. As the other one-way valve I6, which is in the by-pass I3 communicating with the inner end of the cylinder I, will not allow air to escape through port It, air becomes trapped in front of the piston 5 and serves as a cushion to buffer the piston 5 during the latter part of its operative stroke. Deceleration of the piston 5 by this air cushioning action commences immediately following the completion of the shuttle-propelling movement by the picker 9. During the cycle of operation of the distributor valve I8, the rotor 23 rotates through 180 to the position shown in Figure 6, which results in a changeover of the air supply connections. That is, the valve I8 now permits air to be exhausted via the port 42 at the outer end of the cylinder I, through pipe-line I! under the expelling action of the piston 5 during its return movement, and this return movement is brought about, also by action of the distributor valve I8, by the admission of air under pressure to the inner end of the cylinder via the restrictor valve I5, the oneway valve I6 and the port I4, the rate of return of the piston being controlled by the rateof-flow of air past the adjustable valve I5.

The length of the cylinder may be such that acceleration is given to the piston over a comparatively long distance so that a lower rate of piston acceleration may be used to impart to 4 the shuttle the same speed as normally obtained in looms using mechanically-operated pickers or alternatively a higher shuttle speed may be obtained. It will be understood, of course, that a "pneumatic device as above-described is employed at each end of the loom race, the air flow to the two distributor valve being synchronised, by reason of both valves I8 being driven from the same shaft 21, the rotors of the two valves I8 being positioned from each other; that is, one valve rotor is in the position shown in Figure 4 when the other valve rotor is in the position shown in Figure 6.

In the modified arrangement shown in Figures '7 and 8, the cylinder I is mounted beneath an end of the loom race with the longitudinal axis of the cylinder I parallel to the longitudinal axis of the moving shuttle. The piston rod 43 extends out throu h a gland M in that end of the cylinder I which faces outwards, that is, away from the centre of the loom, and on the projecting end 55 of the piston rod 43 the picker 46 is mounted, either fixedly as described in connection with Figure 2, or with a lost-motion connection as described later.

When the piston 41 is at the outer end of its stroke within the cylinder I the packer 46 on the outer end 45 of the piston rod 43 lies in such a position that, when the shuttle 4 has been brought to rest by suitable checking means, including for example swells 48 in the shuttle box 49, and/or by other means, the shuttle 4 is in contact with or substantially in contact with the picker 46.

At the outer end of the cylinder I, that is, the end provided with a gland M for the piston rod 43, an unrestricted air port 58 is provided in such a position that air can be admitted between the piston 41 and the glanded cover 5I at that end of the cylinder I when the piston 51 lies in its outstroke position. At the inner end of the cylinder another unrestricted air port 52 is provided, but in this case the port 52 is situated at some distance in from the cover 53 at that end of the cylinder I. The length of the piston 41 is such, however, that this unrestricted air port 52 is blocked by the piston 4'! when in its extreme instroke position, as indicated by dotted lines in Figure 8. Between the unrestricted air port 52 at the inner end of the cylinder and the cover 53 another air port 54 is provided and this is connected by a by-pass branch 55 to the pipe-line 56 extending from the unrestricted air port 52. The by-pass branch 55 incorporates an automatic one-way or non-return spring-biased valve 51 which allows air to enter but not to leave the cylinder I, through the air port 54.

The pipe-line 56 to which is connected the by-pass branch 55 incorporating the one-way valve 51, and the unrestricted air port 55 at the inner end of the cylinder are connected by pipelines II], I! respectively to appropriate ports in the housing of a rotary distributor valve I8 of the general form shown in Figures 4, 5 and 6, which, as already described, functions to change over the connections between the inner and outer ends of the picker cylinder and a pressure air inlet port 35 and an exhaust outlet port 3| provided in the wall of the valve chest. Preferably, as shown in Figure 10, this rotary distributor I8, incorporates an adjustable restrictor valve 58 associated with the passage 45 in the valve rotor 23 so that the flow of air to the inner end of the picker cylinder I for effecting the outstroke or return movement of the piston 47 can be regulated so that the. picker 46 reaches its end of stroke position just as the shuttle 4 reaches that end of the loom race 59.

It will be readily understood from the fore going description that when, under the controlling action of the rotary distributor valve l8, air under pressure is admitted to the outer end of the cylinder I through the unrestricted air port 50 at that end, the piston 41 is rapidly moved toward the other, that is, the inner end of the cylinder l, air in front of the moving piston 41 being expelled through the unrestricted air port 52 at the inner end of the cylinder I. As the piston 41 nears the end of its instroke movement it blocks the unrestricted air port 52 and since the air remaining in the cylinder cannot escape through the second air port 54 air is trapped in the cylinder end and forms an air cushion which buifers the piston movement. From or just after the commencement of the instroke movement of the piston the picker 46 is in contact with the shuttle 4 which is thereby moved from its position of rest and thrown across the loom race 59. During the period in which the thrown shuttle 4 moves across the loom race 59 and is thrown back by the picker unit on the other side of the loom the distributor valve l8 rotates to cut off the supply of pressure air to the outer end of the cylinder and causes air to flow into the pipe line 56 connected to the inner end of the cylinderl Admission of air to the cylinder interior through the unrestricted air port 52 at that end of the cylinder is temporarily prevented by the blocking of that port by the piston 4'! now lying in its instroke position. Accordingly air first enters the inner end of the cylinder through the port 54, via the one-way valve 5? in the by-pass branch 55 of the pipe-line 58 until such time as the piston 4'! has uncovered the unrestricted air port 52, whereafter air flows directly through that port and the by-pass valve 51 shuts automatically.

Means are shown in Figures 7, 8 and 9 for buffering the picker 46 at both ends of its stroke. In the arrangement illustrated the picker 46 is slidably suspended on a guide rod 66 mounted parallel to the line of travel of the end 45 of the piston rod 43 which extends endwise from the cylinder l. The lower part of the picker 46 is provided with a gap 6| tov form a pair of longitudinally spaced lugs 62, 63 having therethrough aligned

holes

64, 65 respectively within which the piston rod end 45 is slidable. A collar 66 is secured on the rod end 45 so as to lie Within the gap 6|, so that a lost-motion connection is provided which permits of axial movement of the piston rod 43 relatively to the picker 46 to an extent equal to the width of the gap 61 in the picker 46 less the thickness of the collar 66 on the piston rod 43. On the same longitudinal axis as that of the direction of movement of the shuttle 4 a plunger 61 is mounted for endwise movement within a housing 68 fixed above the level of the loom race 59, one end of the plunger projecting outwards for contact with the picker 46 when it is in its outstroke position. Movement of the plunger 61 into the housing 6.8 is efiected against a fluid cushion (air or liquid) which leaks from one side of the head 69 of the plunger 6! to the other side. A coiled compression spring is placed behind the plunger 61 for the purpose of urging it outwards after a shuttle picking movement. When the piston 41, after a shuttle-propelling movement, is returned to its outstroke position for the purpose of setting the picker 46 in readiness for th next picks action the p ker 46 is carried forward by the piston rod collar 66 until the picker 46 conacts with h projecting end of the check plunger 61. The picker check is intended to augment the checking action exerted on the oncoming shuttle 4 by the checking swells 48 provided in the shuttle box 49. The shuttle 4 contacts the picker 46 and forces it rearwardly against the resistance of the check plunger 61, the extent of movement of the shuttle 4 in contact with the picker 46 being equal to the allowable lost-motion movement. When the piston 4! begins its next shuttle-propelling movement the picker 46 moves with the piston. The piston 41 is brought to rest by the air cushion in the cylinder I, but the picker 46 continues its movement relatively to the arrested piston 41 until said picker 46 is checked by a suitable buffer H, such as a rubber block.

I claim:

1, In a loom having a shaft continuously rotating synchronously with the swinging movements of the loom sley, the employment of a loom picking motion comprising two pneumatically-operated shuttle-driving units mounted one at each end of the loom sley race, each unit comprising a horizontally disposed closed air cylinder arranged to extend longitudinally beyond the end of said loom race, a piston slidable in said cylinder with one end of the rod of the piston outside said cylinder and directed toward the centre of the loom sley race, said cylinder having ports for the admission of air under pressure to opposite ends of said cylinder to move the piston in the shuttle-propelling direction and to return the piston to the outer end of its stroke after the shuttle-propelling stroke and said cylinder and said piston co-operating to provide a cushion of air to buiIer the piston at th end of the shuttle-propelling stroke, a picker on said projecting piston rod end, and valve means associated with the cylinder for controlling the admission to opposite ends of the cylinder at appropriate times of air under pressure and for regulating the rate of flow of air to the cylinder for returning the piston to the outstroke position after its shuttle-propelling movement, so that said piston returning movement is eirected at a slower rate than that of the shuttle-propelling movement of said piston, in combination with rotary distributor valve means, one for each unit, both of said distributor valve means being connected to. said continuously rotating shaft so that the shuttle-driving strokes are effected in alternating sequence.

2. A loom picking motion according to claim 1, wherein the means for providing a cushion in the cylinder comprises a cylinder having first and second ports, said first. port at some distance in from that end of the cylinder in which the piston lies when at, the end of its shuttle-propelling stroke to provide a cushioning space wherein air is trapped to. cushion the piston as it approaches the end of said stroke and a second port leading into said space and connected to a ipe-line supplying pressure air to said second port by means of a branch pipe, a first non-return valve connected to said first port to allow air to be expelled therethrough from said cylinder but to prevent pressure air gaining access into the space in the cylinder interior on the inner side of the piston afterit. has passed said first port, a second non-return valve in said branch pipe to prevent the escape of trapped air from said cushioning space but to allow pressure air to flow 7 V r s thereinto at the commencement of the return stroke of the piston, an adjustable restrictor device in said first non-return valve for regulating the flow of air to the cylinder cushioning space.

3. In a loom having a shaft continuously rotating synchronously with the swinging movements of the loom sley, the employment of a loom picking motion comprising two pneumatically-operated shuttle-driving units mounted one at each end of the loom sley race, each unit comprising a closed air cylinder mounted horizontally beneath and parallel to said sley race, a piston slidable in said cylinder with one end of the rod of the piston outside said cylinder and directed outwards from the centre of the loom sley race, said cylinder having ports for the admission of air under pressure to move the piston in the shuttle-propelling direction, for the admission of air under pressure to return the piston to the outer end of its stroke after the shuttle-propelling stroke and for providing a cushion of air to buffer the piston at the end of the shuttle-propelling stroke, a picker on that end of the rod of the piston which is outside said cylinder, said cylinder and its associated piston combining to bring the incomin shuttle to rest in contact substantially with the picker when said piston is at the outer end of its stroke, and valve means associated with the cylinder for controlling the admission thereto at appropriate times of air under pressure and for regulating the rate of flow of air to the cylinder for effecting the return of the piston to the outstroke position after its shuttle-propelling movement at a rate of movement which is less than that during the shuttlepropelling movement, in combination with rotary distributor valve means, one for each unit, both of said distributor valve means being connected to said continuously rotating shaft so that the shuttle-driving strokes are effected in alternating sequence.

4. A 100m picking motion according to claim 3, wherein the picker is slidable to a limited extent along the piston rod and is adapted to continue movement after the piston reaches its outstroke position to the amount allowed by the lostmotion connection between the piston rod and *the picker, said continued movement of the picker resulting from the impact thereon or the incoming shuttle and being effected against the resistance of a buffer means which brings the picker and shuttle to rest.

5. A loom picking motion according to claim 3, wherein each rotary distributor valve comprises a cylindrical housing having spaced ports therein for connection by pipeline to opposite ends of the assoicated cylinder and with similarly spaced ports therein for connection to a source of air pressure and for venting to atmosphere, and a cylindrical plug-like rotor rotatably mounted in said housin and having an extending shaft for deriving rotary power from said continuously rotating loom shaft which moves synchronously with the movements of the loom sley, said rotor having passages therein for connecting in alternating sequence as the rotor revolves the housing ports leading to opposite ends of the cylinder with the air supply and the vent to atmosphere respectively.

6. A loom picking motion according to claim 5, wherein the said rotor carries an adjustable restrictor device for regulating the flow of air to the cushionin space of the associated picker unit cylinder.

'7. In a loom having a shaft continuously rotating synchronously with the swinging movements of the loom sley, the employment of a pneumatically-operated loom picking motion comprising two shuttle-driving units mounted one at each end of the loom race, each unit comprising a closed air cylinder, a piston slidable in said cylinder and a picker on that end of the rod of the piston which is outside said cylinder, said piston and cylinder co-operating to provide an air cushion for checking movement imparted to said picker by the incoming shuttle to bring it to rest in contact substantially with said picker when said piston is at the end of its shuttlechecking stroke and said cylinder having ports for the admission of air under pressure to move said piston therein in the shuttle-propelling direction, for the admission of air under pressure to return said piston toward the end of its shuttle-propelling stroke and for providing a cushion of air to buffer the piston at the end of said shuttle-propelling stroke, valve means associated with said cylinder for controlling the admission thereto at appropriate times of air under pressure and for regulating the rate of flow of air to said cylinder for returning the piston to the outstroke position after its shuttle-propelling movement, in combination with rotary distributor valve means, one for each unit, both of said rotary distributor valves being connected to said continuously rotating shaft so that the shuttle driving strokes are effected in alternating sequence.

8. A loom picking motion according to claim 7, wherein the means for providing an air cushion in the cylinder comprises a cylinder having first and second ports, said first port being some distance in from that end of the cylinder in which the piston lies when in its outstroke position, to provide a cushioning space wherein air is trapped to cushion said piston as it approaches its outstroke position, and said second port leading into said cushioning space and being connected to the pipeline supplying pressure air to said first port by means of a branch pipe, a first non-return valve in the pipeline supplying pressure air to said first port, said first non-return valve allowing air to be expelled therethrough from the cylinder but preventing pressure air gaining access into the space in the cylinder interior on the inner side of said piston when it has passed said first port, and a second non-return valve which prevents the escape of trapped air from said cushioning space but allows pressure air to flow thereinto at the commencement of the return srtoke of the piston.

BARBIE HEATH.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 717,965 Blundell Jan. 6, 1903 921,406 Hunt May 11, 1909 921,658 Bachman May 18, 1909 1,007,733 Rhodes Nov. 7, 1911 1,847,584 Winters Mar. 1, 1932 1,945,238 Sumner Jan. 30, 1934 2,354,340 Utter July 25, 1944 FOREIGN PATENTS Number Country Date 17,435 Great Britain of 1909 586,632 Germany Oct. 24, 1933