GB2181756A - Apparatus for cutting or marking sheet material - Google Patents

Abstract

The apparatus comprises a working surface (20) and a head (16) which is pivotable into and out of contact with the surface (20). The head (16) is provided with a cutting or marking element for providing a cut or marked pattern on a sheet of material on the surface (20). The marking element is releasably retained on the head by locking means (40) at one edge and locating means at the other. The locking means comprises pins (60) which project through holes in the element to prevent movement of the element in a direction perpendicular to the pins (60), and a retaining member (66) which prevents displacement of the element away from the head (16). The pins (60) and the retaining member (66) are operable together by a common operating handle (50). <IMAGE>

Description

SPECIFICATION Apparatus for cutting or marking sheet material This invention relates to apparatus for cutting or marking sheet material and is particularly, although not exclusively, concerned with apparatus for marking stitching lines on leatherduringthemanu- facture of footwear and other leather goods.

During the manufacture offootwear, cut-out leather components are marked at the places where they are to be stitched. The stitching may be forsecuring different components together, or it may befor decorative purposes. Conventionally, this marking is performed by a marking plate which can be pivoted from a first position, in which it lies on an ink pad, to a second position in which it lies on the leatherto be marked, so as to transfer inkto the leather in the appropriate places. Different footwear requires different markings, and so the marking plate is mounted releasably in a head, so that a marking plate app ropriatetothejob in hand can befitted. Conventionally, the head is provided with two grooves atop- posite sides into which the marking plate can be slid.

A locking device is provided for retaining the inserted marking plate in position. A disadvantage ofthis construction isthat all marking plates must have the same lateral dimensions in order to fit the grooves, and thatthese side edges must be machined veryaccurately in orderto prevent any lateral play ortilting ofthe marking plate. Consequently, even marking plates for making relatively small markings must havethe same size asthosefor making relatively large markings. As a result, marking plates tend to comprise two components which are laminated together, thefirstcomponent being machinedtofit the grooves in the head, and the second component beingsomewhatsmallerthanthefirstcomponent and being provided with marking elements fortrans ferring inktothe leather.

According to the present invention there is prov ided a ppa ratus su ita ble for cutting or marking sheet material, the apparatus comprising a displaceable head and a cutting or marking element which is releasably connected to the head, the cutting or marking element being engaged by locating means provided on the head at one side of the element and locking means provided on the head at an opposite side ofthe element, to prevent displacement ofthe element relatively to the head, the locking means comprising a retractable pin preventing displacement ofthe element in directions perpendicularto the length ofthe pin and a retractable retaining member preventing displacement of the element in the lengthwise direction ofthe pin, the pin and the retaining member being operable together by a common operating member.

Preferably, the locking means is operable manually by a handle. The locking means may comprise a part which is displaceable by the handle relativelyto the restofthe head, to which part the pin is fitted.

This part may also carry a cam which acts on the retaining member. The retaining member may be spring loaded into a position in which it releases the cutting or marking element, the cam then overcoming the spring loading in orderto displace the retaining member into engagementwith the cutting or marking element. The pin may be one of two similar pins mounted on the displaceable part, these pins being spring loaded, like the retaining member, inthedir- ection to release the cutting or marking element. The locking means may, for example, comprise a first blockwhich is secured to the head, and a second block which is displaceable towards and away from the first block and is spring loaded in the direction away from the first block.The handle may be operat ive to displace the second blocktowards the first block against the spring loading. The pin or pins may be mounted on the second block to extend through the first block and the head sothat, when the locating means is operative, the pin or pins projects from the head to engage the cutting or marking element. The cam may be secured to the second block to engage a followerwhich is connected by rods extending through the first blockto the retaining member.

The locating means may comprise a groove in the head within which an edge region of the cutting or marking element may be received. Locating pins may be provided in the region ofthegrooveforen- gagement with recesses in the edge region of the cutting or marking elementto preventdisplacementof the cutting or marking element in lengthwise direction ofthe groove.

The present invention also provides a cutting or marking element suitablefor use with apparatus as defined above, the cutting or marking element being provided with recesses and openings for engage- mentwith the locating means and the locking means.

For a better understanding ofthe present invention, and to show how it may be carried into effect, reference will now be made, byway of example, to the accompanying drawings, in which: Figure lisa perspective view of a working station for leather marking; Figure2 is a perspective view of leather marking apparatusforuseattheworkstation of Figure 1; Figure3 is a side view of the leather marking apparatus of Figure 2; Figure 4 is a plan view ofthe leather marking apparatus of Figure 3; Figure 5 is a front view ofthe leather marking apparatus of Figure 4; Figure 6 is a viewtaken in the direction of the arrow VI Figure4oflocking means ofthe apparatus;; Figure 7 is a view taken in the direction of the arrow VII in Figure 6; Figure 8corresponds to Figure 7 but shows the locking means in a different condition; Figure 9 is a diagrammatic sectional view taken on the arrow IX-IX in Figure4; Figure 10 is a view taken in the direction ofthe arrowX in Figure 9.

The work station shown in Figure 1 comprisestwo cabinets 2 and 4 interconnected by a table 6. The table6 supports apparatus 8for marking leather. The apparatus 8 is shown more clearly in Figures 2 to 10, but Figure 1 shows a pedal lOforassisting operation of the apparatus 8, this pedal constituting a modifica tion ofthe apparatus shown in Figures 2 to 10.

The cabinets 2 and 4 are provided with pigeon holes 12 for receiving either material to be worked on or marking platesforfitting tothe apparatus 8, aswill be mentioned later in this description.

The apparatus, as shown in Figure 2, comprises a base 14 and a head 16. The base comprises an inking surface 18, which may be provided with an ink pad, and a working surface 20 for supporting material, such as leather, which is to be marked by the apparatus 8. Although not shown, the working surface 20 may be provided with templates orotherlocating means for properly positioning material on the sur- face 20.

The head l6isconnectedtothebasel4byfour links 22. Each link 22 is connected to the head 16 by a single row ball bearing 24 and to the base plate 14 by double ball bearings 26, in orderto resist lateral displacement ofthe head 16 relatively to the base 14.

The base 14,the head 16 and the links 22 provide a parallelogram linkage which ensures that the head 16 remains substantially parallel to the inking surface 18 andtheworking surface 20 during its operative movement, as will be described later.

The working surface 20 is vertically adjustable by means of a knob 28, in orderto compensate format- serial of different thicknesses. Adjustment by the knob 28 thus enables the upper surface of the material to be always at the same height with respect to the remainder of the base plate 14, regardless ofthethick- ness ofthe material. The base plate 14 is provided with two upwardly projecting dowels 30 for engage mentwith holes 32 in the head 16when the head 16 is in a marking position, as will be discussed later.

The head 16 is provided with a marking plate 34 which is rigidly but releasably secured to the head 16.

As shwon in Figures 9 and 10, one edge region ofthe marking plate 34 is received in a groove 36 atthe rear edge ofthe head 16. Cylindrical pegs 36 are distributed at intervals along the groove 34, and recesses 38 in the marking plate 32 fit over the pegs 36 to retain the marking plate 32 against displacement lengthwise ofthe groove 34.

The other edge region of the marking plate 32 is held securely by a locking device 40 at the front edge of the head 16. The locking device 40 is shown in greater detail in Figures 6 to 8, and comprises a lower block 42 attached to the head 16 and an upper block 44. The upper block 44 is guided for displacement relativelyto the lower block 42 by guide rods 46 which are surrounded by compression springs 48, biassing the upper block 44 away from the lower block 42. The upper block 44 can be displaced towards the lower block 42 against the pressure exerted by the springs 48 by means of a lever 50 which is pivotably supported on a shaft 52 extending between two lugs 54 mounted on the lower block 42. The upper block 44 is suitably recessed to receive the I ugs 54.The handle 50 is provided with a cam surface 56 which engages a hardened steel plate 58 inset into the upper surface of the upper block 44 (Figure 4).

Two locating pins 60 are fixed to the upper block 44 and extend through passages 62 and 64 in the lower block 42 and the head 16, respectively.

A retaining member 66 is mounted on the lower block 42. The retaining member 66 is provided with two rods 68 which extend through passages 70 in the lower block 42, and are interconnected attheirends away from the member 66 by a bar 72. Compression springs 74surroundthe rods 68 and act between the lower block42 and the retaining member 66 to bias the retaining member66awayfromtheblock42.A cam plate 76 is secured to the upper block44and has a cam surface 78 which engages the bar72.

As shown in Figures 3 to 5, the head 16 is provided with a handle 80. The handle 80 may be used instead of, or in additionto,the pedal lOto operate the apparatus.

For operation, a piece of leather to be marked,for example a component of an item offootwear, is located on the working surface 20, and the head 16 is displacedfrom the inking surface 18 ontothe leather on theworking surface 20, so astotransferinkfrom the inking surface 1 8to the leather. The head is positioned accurately on the leather by cooperation between the dowels 30 and the holes 32. The marking element is provided with upstanding metal strips for marking the leather in the appropriate places. The marking element is secured to the head by the locating means constituted by the groove 34 and the pegs 38, and by the locking device 40.The pins 60 ofthe locking device 40 engage openings 82 in the marking element 32, so preventing displacement of the marking element32 in directions perpendiculartothe length of the pins 60. Furthermore, the retaining member 66 extends beneath the marking plate 32 to prevent displacement of the marking plate 32 in the lengthwise direction of the pins 60. Figure 7 shows the locking device 40 in the position in which it engages a marking plate (not shown). To release the marking plate 32, for example if it is desired to replace one marking plate by another, the handle 50 is pivoted by hand in the direction indicated bythe arrow 86 in Figure 6, which allows the upper block44 to rise underthe pressure of the springs 48, so with- drawing the pins 60 from the openings 82.Atthe same time,the cam 76 rises with the upper block 44 from the position shown in Figure 7 to the position shown in Figure 8. This movement allows the bar 72 to move to the right, as shown in Figures 7 and 8, underthe action of the bar 72 by the rods 68,thus also moves to the right, releasing the marking plate 32, which can then be pivoted downwardly at the edge adjacent the locking device 40 and released from the groove 34. Attachmentof another marking plate is accomplished by engaging the recesses 38 at one edge with the pegs 36, that edge region then entering the groove 34. The opposite edge is raised into contact with the front edge of the head 16, and the lever 50 is pivoted in the direction opposite the arrow 86, to press down the upper block 44, causing the pins 60to engage the openings 82, and causing the retaining member 66 to move to the left from the position shown in Figure 8to engage beneath the marking plate32.

It will be appreciated from Figure 1 Othat, as well as full width marking plates 32, narrower marking plates, as indicated by the dashed lines88, can be reliably secured to the head 16, although only two recesses38would beprovidedforengagementwith the inner pair of pegs 36.

Although the present invention has been descri bed by reference to apparatus for marking leather priorto stitching along the marked lines, it will be appreciated that the apparatus could also be used for marking material otherthan leather, and for oper ationsotherthan marking,forexampleforcutting or creasing.

Claims (17)

1. Apparatus suitable for cutting or marking sheet material, the apparatus comprising a displaceable head and a cutting or marking element which is releasably connected to the head, the cutting or marking element being engaged by locating means provided on the head at one side of the el ementandlocking means provided on the head atan opposite side of the element, to prevent displacement of the element relatively to the head, the locking means comprising a retractable pin preventing displacement of the element in directions per pendiculartothe length of the pin and a retractable retaining member preventing displacement ofthe element in the lengthwise direction ofthe pin, the pin and the retaining memeber being operable together buy a common operating member.

2. Apparatus as claimed in claim 1, in which the locking means is operable manually by a handle.

3. Apparatus as claimed in claim 1 or 2, in which the locking means comprises a partwhich is displaceable bythe handle relatively to the restofthe head, to which part the pin is fitted.

4. Apparatus as claimed in claim 3, in which the displaceable part also carries a cam which acts on the retaining member.

5. Apparatus as claimed in claim 4, in which the retaining member is spring loaded into a position in which it releases the cutting or marking element, the cam being disposed to overcome the spring loading in orderto displace the retaining member into engagementwith the cutting or marking element.

6. Apparatus as claimed in any one ofthe preceding claims, in which the pin and the retaining member are displaceable respectively in mutually perpendicular directions.

7. Apparatus as claimed in any one ofthe preceding claims, in which the pin is one of two similar pins mounted on the displaceable part.

8. Apparatusasclaimed in anyoneofthepreced- ing claims, in which the or each pin is spring loaded in the direction to release the cutting or marking element.

9. Apparatus as claimed in any one ofthe preceding claims, in which the locking means comprises a first block which is secured to the head, and a second block which carries the pin or pins and is dis placeabletowardsandawayfromthefirstblockand isspring loaded in the direction awayfrom thefirst block.

10. Apparatus as claimed in claim 9, in which the handle is operative to displace the second blocktow ardsthefirstblockagainstthespring loading.

11. Apparatus as claimed in claim 9 or 10, in which the or each pin is mounted on the second block to extend through the first block and the head so that, when the locating means is operative, the or each pin projects from the head to engage the cutting or marking element.

12. Apparatus as claimed in any one of claims 9 to 11, when appendantto claim 4, in which the cam is secured to the second blocktoengageafollower which is connected by rods extending through the first blockto the retaining member.

13. Apparatus as claimed in anyoneofthepreceding claims, in which the locating means comprises a groove in the head within which an edge region ofthe cutting or marking element may be received.

14. Apparatus as claimed in claim 13, in which locating pins are provided in the region of the groove for engagement with recesses in the edge region of the cutting or marking element to prevent displacement ofthe cutting or marking element in the lengthwise direction of the groove.

15. Apparatus suitable for cutting or marking sheet material, substantially as described herein with reference to, and as shown in, the accompanying drawings.

16. A cutting or marking element suitablefor use with apparatus in accordance with any one of the preceding claims, the cutting or marking element being provided with recesses and openings for engagement with the locating means and the locking means.

17. Acutting or marking element as claimed in claim 16 and substantially as described herewith with reference to, and as shown in, Figures 9 and 10 of the accompanying drawings.