IES70054B2 - Method and apparatus for manufacturing beds - Google Patents

Abstract

A method for assembling mattresses includes attaching insulating padding to a spring unit, glueing layers of filler material to the padded spring unit, glueing upper and lower quilted panels to the unit, attaching flange material to the borders of the spring unit and sewing the panels to the flange material. Sewing is performed on a platform table having at least one tape-edging machine when the rate of sewing is decreased for sewing the corner portion of the mattress. Pre-selected speeds are chosen for sewing along straight edges and for the corner portions. A method for assembling a bed base includes providing a drawer bay which retains a storage drawer flush with the metal runners to support the drawer and to facilitate free movement of the drawer into and out of the bay.

Description

METHOD AND APPARATUS FOR MANUFACTURING BEDS The present invention relates to a method for manufacturing beds and more particularly to an improved method of assembling mattresses and bed bases.

The present invention provides a method of assembling a mattress comprising a spring unit, insulating padding, layers of filler material, flange material and upper and lower mattress panels, the method including the steps of: attaching insulating padding to the spring unit; glueing layers of filler material to the padding covering the spring unit; glueing the upper and lower mattress panels to the spring unit; attaching flange material to the borders of the spring unit; and sewing the mattress panels to the flange material, the rate of sewing of the mattress panels to the flange material being decreased for sewing the corner portions of the mattress by pre-selecting at least two sewing speeds, a first speed for sewing along straight edges and a second relatively slower speed for sewing the corner portions of the mattress.

Advantageously, sewing is performed utilising a tape-edging machine.

Advantageously, the tape-edging machine is controlled without utilising an assembler-controlled clutch mechanism by a speed control means incorporating a start/stop switch.

The method of assembling a mattress may have several steps including: transferring raw material from a storage area to an assembly area; placing the spring unit on a rotatable work platform for padding; glueing filler material and the mattress panels to the spring unit; sewing the panels and flange to the spring unit on the platform with a tape-edging machine to complete the assembly of the mattress; and transferring the assembled mattress to a quality control station for subsequent labelling and bagging for transportation from a loading area.

The method of assembling a mattress may include assembling a bed base for said mattress comprising a base frame, hardboard panels, corner supports, padding material and upholstery fabric, the method of assembling the base including the steps of: r mounting the frame on a work platform; • · reinforcing the frame with corner supports; attaching the hardboard panels to the frame; and stapling the padding material to be frame; < providing a drawer bay in the frame, the bay including a plurality of metal runners to support a drawer and facilitate free movement of the drawer into and out of the bay.

Advantageously, the drawer is disposed bay so as to position the drawer floor flush with the bottom edge of the base.

The invention also provides apparatus for use in the manufacture of mattresses and/or bed bases, the apparatus comprising a plurality of conveyors including first and second conveyors, the second conveyor being supported above and parallel to the first conveyor to form an accumulator in the conveyor belt line of first conveyors.

Advantageously, the accumulator is disposed in an assembly area between a storage area where raw material is stored and a loading area where assembled articles are labelled and bagged for shipping.

Advantageously, the apparatus includes a conveyor for transporting raw material from the storage area to the assembly area, the conveyor having an inclined portion so that materials can be conveyed from a storage area which is . at a different level than the assembly area.

* Advantageously, each conveyor comprises a support frame, an endless belt, a pair of end rollers, at least one intermediate roller and a drive means, in which identical parts are used for each conveyor so that only a limited stock of spare parts is required.

Advantageously, the drive means comprises a motor mounted to the support frame below the plane of the conveyor, the motor acting Upon the leading end roller by a sprocket and i chain drive.

Advantageously, at least one roller is adjustably mounted on the support frame so that tension in the endless belt of each conveyor is variable.

Advantageously, platform tables are provided adjacent the conveyors from which raw materials are taken for assembly on the tables, the assembled articles being loaded back onto the conveyors for transferring to subsequent assembly stations.

Advantageously, the platform tables are revolving tables to allow easy manipulation of the article being assembled and are provided with hinged portions to allow the table width to be altered.

The invention will now be described more particularly with reference to the accompanying drawings which show, by way of example only, a method for manufacturing beds according to the invention. In the drawings: Figure 1 is a perspective view of a first conveyor for transferring new materials from a storage facility towards an assembly area; * Figure 2 is a perspective view of a second conveyor disposed on an incline to transfer raw materials from the first conveyor to the assembly area.

Figure 3 is a perspective view of a third conveyor, fed from the second conveyor, from which raw materials are taken for transfer to work platforms; Figure 4 is a perspective view of a fourth conveyor disposed over the third conveyor; and Figure 5a and 5b show side elevations of a prior art bed base and a bed base modified according to the present invention, respectively.

Referring to the drawings and initially Figures 1 to 4, a 10 conveyor belt line is provided from the storage area to the work area on a factory floor. The conveyor belt line allows employees to transport heavy raw materials from the storage area to the factory floor where previously all heavy raw materials had to be manually transported. The conveyor belt line vastly improves production output and decreases the incidence of injury. Additionally, due to the traditional methods used, the vast majority of workers on the factory floor were males. The conveyor line allows an employer to employ more female members of staff to perform various jobs that were once male dominated.

The conveyor belt line runs from the storage area, onto the factory floor and continues along the factory floor to a loading area where completed bedding products are stored. The conveyor line is split into four different conveyors 10,20,30,40 with a separate motor M running each conveyor belt 50. Three of these conveyors run from the storage area to the loading area, covering a distance of 52 metres (170ft). The first conveyor 10 runs directly through the storage area covering a distance of 11.25 metres (37ft). It is on this first conveyor 10 that a store man forwards the various raw materials needed on the factory floor. A forklift would normally be provided for the store man for loading the heavier raw material on the first conveyor. A production manager on the factory floor normally contacts the store man via an intercom device or other communication means such as a mobile telephone to $. order the raw materials to the factory floor on a just-in time basis. There is no necessity for any other employees to enter the storage area when the conveyor belt line is in operation.

The second conveyor 20 in the line is disposed between the storage area and the factory floor. This section is 23m (75ft) in length, the first 10.7m (35ft) of which is inclined upwards at an angle of 25 degrees to facilitate the situation where the factory floor is at a higher level to the storage area. A tunnel may often be found between a storage area and a factory floor and the provision of a conveyor therethrough provides obvious advantages.

The third conveyor 30 is provided from the end of the second conveyor 20 to the loading area. This conveyor covers a distance of 17.7m (58ft). A labelling and bagging operation conveniently takes place at the end of the third conveyor 30. When the various assembled products are bagged and labelled they are stacked on trolleys (not shown) which have a frame of approximately 1.8m x 2.15m (6ft by 7ft) attached to them. These trolleys are designed especially for the purpose of easily moving the finished products to their designated locations in the loading area. Consequently, one employee can bag and label all the assembled products efficiently.

The conveyor line, comprising the above three conveyors ' I· ,20,30, is situated at a height of 76cm (30 inches) from floor level. The fourth conveyor 40 of the conveyor line is installed after the first three conveyors 10,20,30 and is situated directly above and running parallel to the third conveyor 30. The height of the fourth conveyor from floor level is 152cm (60 inches). This conveyor 40 is provided to cope with overflow of the various assembled or finished products. The conveyor 40 is installed to obviate the need to stop the line at various times due to the build up of assembled or finished products on the third conveyor 30. Any delay on the third conveyor 30 consequently causes a delay transferring the raw materials to the factory floor. The fourth conveyor 40 runs for a distance of 17.7m (58ft) and overlies 3m (10ft) of the second conveyor 20 and 13.7m (45ft) of the third conveyor 30.

Each conveyor 10,20,30,40 in the conveyor line is fitted with the identical parts for ease of construction and servicing. It is only necessary to store a limited number of parts to ensure spares are available for the four conveyors. Each conveyor is provided with an endless belt 50 and a pair of large rollers 52, one at each end of the endless belt 50. The rollers 52 are 28cm (11 inches) in diameter with an axial shaft 54 of 6.35cm (2.5 inches) in diameter. The axial shafts 54 are attached to 9cm (3.5 inch) bearings 56 which in turn are slipped into grooves on a main conveyor frame 59. Attached to each bearing 56 is a long tension adjusting bolt 60. By loosening or tightening the bolt 60, the correct tension on the endless belt 50 can be obtained. At various intervals along each conveyor, smaller rollers 63 are fitted. These rollers are 10cm (4 inches) in diameter and are situated approximately 3m (10ft) apart. The conveyor frames 59 are provided with a series of support legs 65 each having flanges 67 for bolting the legs to the floor.

Each endless belt 50 is powered by a motor M acting on the roller 52 at one end. The motors M are selected to have variable speed production gears, which can be set from 0 8 30rpm. The four motors M required are identical and are 1.5kW (2hp) rated. A 9cm (3.5 inch) sprocket 70 is £ attached to the drive shaft of each motor M. A chain 72 is connected from this sprocket 70 and engages another sprocket 74 with a 25cm (10 inch) diameter which drives the axial shaft 54 of the end roller 52. Each motor M is attached to the frame 59 of the conveyor approximately 23cm (9 inches) above floor level with heavy duty brackets and the distance between the two sprockets is 76cm (30 inches). The motor M on the fourth conveyor 40 is attached to the conveyor frame 59 as before but is situated on the opposite side of the conveyor frame 59 and is 122cm (4ft) above floor level. A guard frame (not shown) is provided around the sprockets 70,74 and chains 72 on all motors M for safety. The conveyor frame 59 is 152cm (60 inches) wide while the endless belt itself 50 is 122cm (48 inches) wide. Emergency stop buttons are placed at regular intervals along the conveyor line.

The method of assembling a mattress includes collecting together at a platform table, a spring unit, insulating padding, layers of filler material, flange material and upper and lower mattress panels. The various raw material provided from the storage area include a mattress spring units, felt pads, polyester filler material, various insulating pads and fittings. The assembly of the various mattress products is performed on one side of the conveyor line. The first procedure is to pad the mattress spring unit with the insulating pad required for the particular mattress being assembled. A special padding gun is f, provided for this procedure. The jaws on prior art padding guns frequently jammed when they came in contact with the insulating pad and the spring unit. This difficulty was caused by the staples entering the jaws of the gun at an incorrect angle, jamming the jaws in use.

This difficulty was ascribed to a staple holder which <j allowed the staples too much movement when entering the jaws of the gun. A spring loaded staple holding means counteracts the above problem. Additional advantages were obtained by increasing the jaws of the gun in size. The padding gun is normally pneumatically powered.

Four revolving platform tables are used on the base assembly line and two on the mattress assembly line. The revolving platform table allows an assembler to upholster a base and pad or glue a mattress while remaining in the same position. When the assembler is finished working on one particular side of a product, it is only a matter of spinning the table around to work on the opposite side.

The tables are also fitted with hinged sides to allow the employee to adjust the table width to suit the different widths of mattresses and bases being manufactured. The table revolves on a bearing having a diameter of 25cm (10 inches).

When the spring unit is padded, it is returned to the conveyor and transported to the next station which includes a glueing table. Various felt and polyester pads are glued on top of the insulting pad at this point depending on the quality of the mattress being manufactured. In standard glueing procedures it is difficult to control the flow of glue coming from a glue gun. Controlling the flow of glue on the existing gun is accomplished by adjusting the air-pressure valve which is situated 9m (30ft) from the glueing table, to isolate the assembler from the source of glue fumes for health and safety reasons. A new glueing gun is provided having a dial situated behind the glue nozzle. This dial can be tuned clockwise or anti-clockwise to adjust the air-pressure in the value without the assembler having to go near the barrel.

The quilted material panels are also glued in position on top of the other pads at this table. The material panels are quilted on a double-head, deep stitch quilting machine. In the double-head, deep stitch quilting machine the material is put on a frame and placed under two sewing heads. The sewing heads remain static while the frame moves around them using a track arrangement disposed below the quilting machine. The frame is connected to the track by a wheel which moves around the track to obtain the design pattern required. The track should be sufficiently narrow and short to allow the material frame to rotate and avoid contact with either of the sewing heads.

After the quilted material tops are glued onto the spring unitr the border flange material is fitted around the unit which is then returned to the conveyor to move the mattress to the next platform table which includes a tape-edging machine. The tape-edging machine sews the quilted material panels to the side flanges, thus completing the mattress assembly. To increase the speed at which the mattresses are sewn, a second tape-edging machine is attached to the platform table. As the corners of the mattress have to be sewn at a slower speed than the straight edges of the mattress, it was found that the assembler could not slow down without using a clutch mechanism provided on the tape-edging machine or without stopping the machine. To overcome this problem, the rate of sewing at the corners is decreased by a pre-selected amount using a speed program for both tape-edging machines. This program consists of two separate speed control switches connected to each tape-edging motor, the switches being mounted on the tape-edging machines within each reach of the assembler. Both switches can be set from 0 - 10rpm. A first switch controls the speed of the motor when the edging machine is on the mattress straight and a second switch controls corner speed. A start and stop button is connected to the same control thus eradicating the need for a clutch. With the new program, the power requirement for the edging machine motor increases from 0.5kw to 0.75kw (0.75hp to 1hp). The platform tables are provided with pneumatic rams so that they can be adjusted up to 23cm (9 inches) in height. This allows the assembler to choose the most comfortable height at which to work. Previously, an assembler would add timber walk-ways around the machine to adjust for the most comfortable work height. When the mattress has been sewn it is returned on the conveyor where it travels to the end of the conveyor line. Quality control checks are completed before the mattress is labelled and bagged and transported to the loading area.

The manufacture of various base products is performed on the right side of the conveyor line. When the base frame arrives from the storage area it is first put on a tracking table. The headboard, inside corner supports and top insulating felt or polyester pads are fixed to the base at this stage. The assembled frame is then returned to the conveyor and transported to an upholstery table. The base is completed on this table. There are two tacking tables and two upholstery tables in operation. One tacking table and one upholstery table are utilised for storage type bases. The remaining two tables are utilised for standard bases. An improved storage drawer is provided which is especially suited to the present bases. A prior art drawer D, as illustrated in Figure 5a, is approximately 15cm (6 inches) in depth and 61cm (24 inches) in width. It is disposed approximately 7.6cm (3 inches) from the bottom F of a 30.5cm (12 inch) base. A common complaint with the standard storage drawer D is that the drawer is too small and is difficult to move when 6 loaded as they run on wooden batons tacked to the drawer bay B. The base 100 of the present invention is provided with a drawer 110 which is adapted to run on metal runners which allow the drawer floor 111 to be flush with the bottom 101 of the 30.5cm (12 inch) base 100, as shown in Figure 5b. The storage drawer 110 now has a much larger capacity having a 23cm (9 inch) depth and a width of 76cm (30 inches). The newly designed drawer 110 is slotted into two aluminium runners (not shown) which are screwed onto the inside of the drawer bay 103 in the base. These runners allow the drawer to move more freely with heavier loads which previous timber runners did not allow. At the upholstery tables the base covers are fitted onto the bases followed by headboard bolts, polypropylene, castors, cardboard corner protectors and linked bars. The bases are then returned on the conveyor belt and travel to the end where a quality control check is performed before the bases are bagged and dispatched to the loading area.

Each completed bed base is combined with a completed mattress to form a completed bed unit for sale to a customer.

It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention as defined in the appended claims.

Claims (5)

1. A method of assembling a mattress comprising a spring unit, insulating padding, layers of filler material, 5 flange material and upper and lower mattress panels, the method including the steps of: attaching insulating padding to the spring unit; 10 glueing layers of filler material to the padding covering the spring unit; glueing the upper and lower mattress panels to the spring unit; attaching flange material to the borders of the spring unit; and sewing the mattress panels to the flange material, the 20 rate of sewing of the mattress panels to the flange material being decreased for sewing the corner portions of the mattress by pre-selecting at least two sewing speeds, a first speed for sewing along straight edges and a second relatively slower speed for sewing the corner portions of 25 the mattress; optionally, in which sewing is performed utilising a tape-edging machine; 30 optionally, in which the tape-edging machine is controlled without utilising an assembler-controlled clutch mechanism by a speed control means incorporating a start/stop switch; and 35 optionally, including: transferring raw material from a storage area to an c assembly area; 5 placing the spring unit on a rotatable work platform for padding; glueing filler material and the mattress panels to the spring unit; sewing the panels and flange to the spring unit on the platform with a tape-edging machine to complete the assembly of the mattress; and 15 transferring the assembled mattress to a quality control station for subsequent labelling and bagging for transportation from a loading area.

2. A method of assembling a mattress as claimed in any 20 one of the preceding claims including assembling a bed base for said mattress comprising a base frame, hardboard panels, corner supports, padding material and upholstery fabric, the method of assembling the base including the steps of: mounting the frame on a work platform; reinforcing the frame with corner supports; ·< 30 attaching the hardboard panels to the frame; and L stapling the padding material to be frame; providing a drawer bay in the frame, the bay including a 35 plurality of metal runners to support a drawer and facilitate free movement of the drawer into and out of the 4 bay; and optionally, disposing the drawer bay so as to position the 5 drawer floor flush with the bottom edge of the base.

3. Apparatus for use in the manufacture of mattresses and/or bed bases in accordance with any one of the preceding claims, the apparatus comprising a plurality of 10 conveyors including first and second conveyors, the second conveyor being supported above and parallel to the first conveyor to form an accumulator in the conveyor belt line of first conveyors; 15 optionally, in which the accumulator is disposed in an assembly area between a storage area where raw material is stored and a loading area where assembled articles are labelled and bagged for shipping; 20 optionally, including a conveyor for transporting raw material from the storage area to the assembly area, the conveyor having an inclined portion so that materials can be conveyed from a storage area which is at a different level than the assembly area; optionally, in which each conveyor comprises a support frame, an endless belt, a pair of end rollers, at least one intermediate roller and a drive means, in which identical parts are used for each conveyor so that only a 30 limited stock of spare parts is required; optionally, in which the drive means comprises a motor mounted to the support frame below the plane of the conveyor, the motor acting upon the leading end roller by 35 a sprocket and chain drive; and optionally, in which at least one roller is adjustably mounted on the support frame so that tension in the endless belt of each conveyor is variable.

4. Apparatus according to claim 3, in which platform tables are provided adjacent the conveyors from which raw materials are taken for assembly on the tables, the assembled articles being loaded back onto the conveyors for transferring to subsequent assembly stations; arid optionally, in which the platform tables are revolving tables to allow easy manipulation of the article being assembled and are provided with hinged portions to allow the table width to be altered.

5. A method of assembling a mattress and/or a bed base substantially as herein described with reference to the accompanying drawings or apparatus for use in the manufacture of mattresses and/or bed bases substantially as herein described with reference to and as shown in the accompanying drawings.