GB2051903A - Cloth laying machine - Google Patents

Abstract

Apparatus for regulating the height of the laying element (19) in a cloth laying machine (10) relative to the spread cloth layers (30) includes an elevator carriage (20) supporting the spreader element (19) for vertical reciprocal movement, motor control means (28) for positively driving the elevator carriage (20) upwardly or downwardly relative to the machine frame (11) and a cloth layer sensor device (32) for actuating the motor control means (28) to move the elevator carriage (20) upwardly or downwardly in order to maintain a substantially uniform height (X, Y) between the cloth laying element (19) and the top layer of cloth (30'). The sensor device (32) includes means (33, 34) for discharging or propagating incident rays (I), such as a stream of air, downward upon the immediate area of the top cloth layer (30') and for receiving and transmitting the reflected rays (R) to a transducer (57, 157), Fig. 5 (not shown), for converting the rays (R) to electrical signals for actuating the motor control means (28). Instead of pneumatic sensors (33, 34), a light source and a photoelectric cell or sonar sensing devices may be used. <IMAGE>

Description

SPECIFICATION Cloth spreading machine This invention relates to a cloth spreading machine, and more particularly to an apparatus for regulating the spacing between the cloth spreader element and the cloth layers.

Heretofore, in cloth spreading machines, the height of the spreader blade or spreader element has been adjusted or elevated by various mechanical devices. One common method of elevating the cloth spreader blade is to provide a cam mechanism on the catcher at one end of the cutting table for engagement by the spreader blade to elevate the spreader blade by one increment. Thus, as the cloth spreading machine travels the full length of the cutting table, to and fro, and spreads a sufficient number of layers of cloth, the spreader blade automatically rises a uniform increment of height. Since the compressibility and thickness of the cloth layers varies with the different types of cloth to be spread, the number of layers required to elevate the spreader blade one increment varies.

Another method of elevating the cloth spreader blades is to provide an elevator mechanism which can be raised or ratcheted upward by some type of sensor finger or feeler which is automatically forced upward by the increasing height of the cloth layers. This type of cloth spreader blade elevating mechanism has not been too successful because of the pliability and compressibility of the cloth layers which does not produce uniform spacing between the spreader blade and the top cloth layer.

Another limitation of the conventional elevation of the spreader elements is the fact that the mechanical sensing of cloth layers is affected only at one end of the cloth layers which are severely compressed by the weight of the catcher bar or the weight of the feeler element sensing the height of the top cloth layer.

It is therefore an object of this invention to provide an apparatus for regulating the spacing between the cloth spreader element and the top cloth layer, which is not only more responsive to the height of the cloth layers, but also continuously monitors the height of the cloth layers so that the spreader element is maintained at a substantially uniform height above the top cloth layer at all times.

Another object of this invention is to provide a device for sensing the height of the cloth layers in which there is no physical contact between the sensor element and the cloth layers.

Another object of this invention is to provide a regulating apparatus for the spreader element in which the spreader element may be positively driven upwardly or downwardly in order to maintain a substantially uniform height between the spreader element and the top cloth layer.

The invention provides a cloth spreading machine having cloth supply means and a spreader frame having longitudinal and transverse dimensions movable longitudinally relative to a cloth supporting surface for carrying cloth from said supply means and for spreading the clotl1- longitudinally in layers upon said supporting surface, a spreader height regulating apparatus comprising:: a) a spreader element for receiving and spreading layers of cloth upon the supporting surface; b) elevator means mounting said spreader element transversely of said frame for vertical reciprocal movement; c) motor means for positively driving said elevator means selectively in an upward direction or a downward direction; d) cloth layer sensing means mounted on said spreader element having a sensor device spaced above the cloth layers spread on the supporting surface in operative position, and a control mechanism coupling said sensor device and said motor means; e) said sensing means comprising means for discharging a ray toward said cloth layers, said sensor device receiving the ray reflected from the top layer of cloth; and f) said control means being responsive to the value of the reflected ray to actuate said motor means to maintain a substantially uniform height between said sensor device and said top layer of cloth.

A reversible electrical motor is operatively connected to the elevator carriage for positively driving the carriage either upward or downward until it stops at the proper spacing between the spreader element and the top cloth layer.

The sensor device for controlling the reversible electrical motor is preferably mounted approximately midway across the machine for sensing the middle portion of the cloth layers. The sensor device is provided with means for discharging incident rays downward upon the cloth layers where the rays are reflected back into the sensor device. The reflected rays are converted into electrical signals having values commensurate with the spacing between the sensor device and the top cloth layer. The electrical signals then determine whether the elevator carriage is moved upward or downward in order to maintain the substantially uniform spacing between the spreader element and the top cloth layer.

The invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a fragmentary side elevation of the front portion of a cloth spreading machine incorporating this invention, with portions broken away; Fig. 2 is a fragmentary front elevation of the machine of Fig. 1 taken along line 2--2 of Fig. 1; Fig. 3 is an enlarged fragmentary front elevational view, partially in section, of the sensor element in operative position relative to the cloth layers; Fig. 4 is an enlarged bottom view of one of the sensor elements taken along the line 4 of Fig.

3: and Fig. 5 is a schematic circuit diagram of the sensor controls.

Referring now to the drawings in more detail, Figs. 1 and 2 show a cloth spreading machine 10 having a mobile frame 11 supported by wheels, such as 12, mounted in a track or a rail 13 fixed alongside an elongate cutting table 14.

Supported on the frame 11 is a laterally moveable cloth supply carriage 1 5 supporting a cloth supply roll 1 6. A web of cloth 17 is fed across the top cloth feed roller 1 8 downwardly through a transversely extending cloth spreader element or head 1 9 fixed to an elevator carriage 20.

Fixed to the elevator carriage 20, at each end thereof, is a travelling nut 21 receiving a vertically threaded shaft or screw 22. The upper end of the screw 22 is coupled through a right-angle gear mechanism 23, driven chain and sprocket transmission 24, and drive chain and sprocket transmission 25 to a reversible electrical motor 26.

The electrical motor 26 is controlled through leads 27 from the electrical control apparatus within the control cabinet 28.

The cloth spreader element 1 9 is of a conventional construction extending transversely across the front of the machine 10 to receive and spread the web of cloth 1 7 in layers 30 as the machine 10 moves longitudinally back and forth along the cutting table 14, in a conventional manner.

The sensor device 32 made in accordance with this invention, is mounted on the lower portion of the elevator carriage 20 at any desired transverse position, but preferably midway across the machine 10.

The sensor device 32 includes first and second downwardly projecting sensor elements 33 and 34, of the pneumatic type as disclosed in Figs. 3, 4 and 5.

The sensor element 33 includes a pair of concentric tubes, including an outer tube 35 and an inner tube 36 defining outer discharge ports 37 and a central inlet chamber or port 38. In like manner, sensor element 39 includes an outer tube 135 and a concentric inner tube 136 defining discharge ports and an inner port such as 37 and 38.

Each of the nozzles or pneumatic sensing elements 33 and 34 are secured through the bottom wall 39 of the housing for the device 32 by nuts 40. (Figs. 3 and 4) The nozzle 33 is connected by a flexible hose 41 having an annular outer discharge chamber 42 in fluid communication with the discharge ports 37 and a central tubular inlet conduit 43 in fluid communication with the inlet port 38.

The hose 41 is connected to coupling 45 in such a manner that the annular chamber 42 is connected to branch supply line 46, which in turn is connected through T-coupling 47 to the main air supply line 48. Compressed air is supplied to the main air line 48 from the air supply device 50, such as a compressor.

The inlet chamber 43 of the hose 41 is connected to the smaller air input line 51 to the air amplifier device 52. When the air pressure in the inlet line 51 is great enough, a diaphragm within the air amplifier 52 is moved to open a valve permitting a larger charge of air to be introduced from the input supply line 53 and restrictor 54 for discharge through the air outlet line 55 to the electro-pneumatic switch device 57. The amplified air signal discharged through the outlet line 55 produces a corresponding electrical signal in the electro-pneumatic switch device 57, which is transmitted through the lines 58 to the motor control device 28.Actuation of the motor control device 28 from a signal produced by the air sensor element 33 energizes electrical motor 26 in a direction to cause the elevator carriage 20 to move downwardly until the sensor 33 is at a predetermined spacing X from the top cloth layer 30', in which position the signal produced by the reflected air ray or stream R opens the switch 57 to stop the motor 26.

In a similar manner, hose 141 has its outer annular chamber 142 communicating through coupler 145 to branch air line 146, which is also connected to the T-coupling 47 to receive its charge of compressed air from the main air line 48. The central or inner air chamber 143 of the hose 141 is connected through inlet line 151 to amplifier 152, identical to the amplifier 52.When the diaphragm in the air amplifier 1 52 is open, a charge of air is supplied to the amplifier 1 52 through input supply line 153 and resistor 154, creating an amplified output air charge in the output line 1 55 to tha electro-pneumatic switch device 1 57. The electrical signal from the switch 1 57 is transmitted through lines 1 58 to the motor control 28 to reverse the direction of the motor 26 and cause the elevator carriage 20 to rise until the predetermined uniform spacing Y between the sensor element 34 and the top cloth layer 30' is attained.

It will be noted in Fig. 3 that the spacings X and Y between the bottoms of the respective sensor elements 33 end 34 and the top cloth layer 30' are of slightly different heights and differ by the increment d.

In the operation of the machine 10, the frame 11 moves longitudinally of the table 14 in a reciprocal manner for spreading the cloth web 1 7 in layers 30 in a conventional manner.

In order to maintain the spreader element 1 9 at a substantially uniform distance above the accumulating cloth layers 30, the sensor device 32 is activated by discharging air from the air supply 50 through the main line 48 and branch lines 46 and 146, hoses 41 and 141, nozzles 33 and 34, and the discharge ports 37. These incident rays or streams of air I impinge upon the top cloth layer 30', which reflects the air streams in the form of reflected air streams or rays R toward the inlet port 38. The reflected rays R received by the sensor elements 33 and 34, are transmitted through the inlet tubes 36 and 136 and air chambers 43 and 143 to their respective amplifiers 52 and 1 52.

In initially setting the spreader element 1 9 to its lowermost position before the first layer of cloth is spread, the sensor 33 will normally be at a height greater than the spacing X. The absence of an electrical signal resulting from a weale or nonexistent reflected ray R in the amplifier 52 will condition the switch device 57 to energise the motor control 28 and cause the electrical motor 28 to be actuated to drive the elevator carriage 20 downwardly. As soon as the tip of the nozzle 33 attains a position spaced from the top surface of the cutting table 14, by the height X, an electrical signal generated by an increase in air pressure created by the reflected air ray R received in the sensor 33 will turn off the switch 27 and stop the motor 26.

After the spreading begins, the cloth layers 30 begin to accumulate until the distance between the top layers 30' and the tip of the nozzle 34 is equal to or slightly less than Y. The increased air pressure created by the air ray R received in the sensor nozzle 34 will actuate the amplifier 1 52 to close the switch device 1 57 energizing the motor control 28 to reverse the direction of the motor 26 causing the elevator carriage 20 to rise. As soon as the spacing Y has again been attained or exceeded, then the amplifier 52 will be activated to turn on the switch device 57 to stop the motor 26. If the spacing X is exceeded, the sensor 33 will be actuated to slightly lower the elevator carriage 20 until the distance X is attained.

As the spreading continues and the cloth layers accumulate in height, the above sensing process will be repeated.

The spacing d between the tips of nozzles 33 and 34 is provided to permit a certain null area where a few layers of cloth 30 can be accumulated without activating either of the sensor switches 57 or 1 57.

The sensor device 32 permits continuous monitoring of the cloth layer height to maintain the spreader element 1 9 at a substantially uniform height above the top cloth layer 30' upon instantaneous command. This distance between the spreader element 1 9 and the top cloth layer 30' is maintained at all times, rather than being incrementally changed only at the end of each reciprocal cycle af the spreading operation.

Examples of pneumatic sensor devices 33 and 34 are the PS-307 sensor of AIRT Co. of Troy, Michigan. The electro-pneumatic switches 57 and 1 57 may be SF100 switches of the AIRT Co.; while air amplifiers 52 and 152 may be JAF 161 amplifiers of the same company.

It will be understood that other types of sensors can be used which will emanate incident rays I of various forms of energy to produce reflected rays R of strengths or values varying with the distance of the sensor device from the top cloth layer 30'.

For example, instead of pneumatic sensors 33 and 34, a light source and a photoelectric cell could be used, to produce incident and reflected light rays, sonar sensing devices could be used, as well as other types of devices which propagate other types of energy waves or rays.

Claims (7)

1. In a cloth spreading machine having cloth supply means and a spreader frame having longitudinal and transverse dimensions movable longitudinally relative to a cloth supporting surface for carrying cloth from said supply means and for spreading the cloth longitudinally in layers upon said supporting surface, a spreader height regulating apparatus comprising:: (a) a spreader element for receiving and spreading layers of cloth upon the supporting surface; (b) elevator means mounting said spreader element transversely of said frame for vertical reciprocal movement; (c) motor means for positively driving said elevator means selectively in an upward direction or a downward direction; (d) cloth layer sensing means mounted on said spreader element having a sensor device spaced above the cloth layers spread on the supporting surface in operative position, and a control mechanism coupling said sensor device and said motor means; (e) said sensing means comprising means for discharging a ray towards said cloth layers, said sensor device receiving the ray reflected from the top layer of cloth; and (f) said control means being responsive to the value of the reflected ray to actuate said motor means to maintain a substantially uniform height between said sensor device and said top layer of cloth.

2. The invention according to claim 1 in which said control means comprises means for actuating said motor means to drive said elevator means in an upward direction when the distance between said top cloth layer and said sensor device is less than said uniform height, and for reversing the actuation of said motor means to drive said elevator means in a downward direction when the distance between said top cloth layer and said sensor device is greater than said uniform height.

3. The invention according to claim 2 in which said sensor device comprises first and second sensor elements, said sensing means comprising means for discharging incident rays downward from both of said sensor elements towards said top cloth layer, both said sensor elements being adapted to receive the reflected rays from the top cloth layer, said control means comprising a first control means operatively connected to said first sensor element for actuating said motor means to drive said elevator means in a downward direction only and to stop when the distance between said first sensor element and said top cloth layer is substantially equal to said uniform height, said control means comprising a second control device operatively connected to said second sensor element and adapted to actuate said motor means in the opposite direction for driving said elevator means only in an upward direction until the distance between said second sensor element and the top cloth layer is substantially equal to said uniform height.

4. The invention according to claim 3 in which said incident rays and said reflected rays are streams of air, and said control means comprise electro-pneumatic control means capable of converting the air pressure signals from said reflected air rays into corresponding electrical signals for energizing said motor means.

5. The invention according to claim 4 in which each of said first and second sensor elements and said first and second electro-pneumatic control means comprises means for discharging a stream of air downward upon the top layer of cloth, said sensor device comprising a tubular sensor element for receiving the reflected air stream, said motor means comprising electrical motor means, motor control means for controiling an electrical motor, an electro-pneumatic switch means connected to said motor control means, and air conduit means connecting said sensor tube to said electro pneumatic switch means.

6. The invention according to claim 5 further comprising pneumatic amplifier means in said air conduit means between said sensor tube and said - electro-pneumatic switch means.

7. A cloth spreading maching having a spreader height regulating apparatus, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.