Australian Patents Act 1990 - Regulation 3.2 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title Automatic safety device for quick coupler The following statement is a full description of this invention, including the best method of performing it known to me/us: 5102 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic safety device for a quick coupler, and more particularly, an automatic safety device for a quick coupler used for coupling an attachment with an arm of heavy equipment such as an excavator, 2. Description of the Related Art In general, heavy equipment such as an excavator used at construction work sites or civil-engineering work sites is widely used as construction machinery for road works, water supply and sewer works, building foundations, works of collecting soil and sand, or the like. Various types of attachments may be selectively mounted to the heavy equipment according to the application of work. For example, various types of attachments may be replaced and used for various works such as a digging work using a bucket, a concrete building demolition work and an iron bar cutting work using a crusher, a rock and concrete demolition work using a breaker, a scrap iron and rock moving work using a grab, a mineshaft work using a clamshell bucket, a water supply and sewer work using a clamshell bucket, a building foundation work using a clamshell bucket according to the application of work. The attachment is coupled with the arm of the excavator in a detachable structure so that the attachment can be replaced according to the application of work, Recently, a quick coupler capable of easily coupling the attachment has been developed and widely used. For example, the attachment can be easily treated and used in such a manner that a driver of the excavator manipulates a lever to couple the quick coupler installed at the front end of the arm with a bucket, a breaker, or the like or to separate the quick coupler from the bucket, the breaker, or the like. In addition, a safety device such as a safety pin is installed in the quick coupler in order to prevent a danger of attachment separation caused by disorder or damage of a hydraulic cylinder or a hydraulic hose in the quick coupler during the work and in order to cope with various types of safety accidents. For example, quick couplers with a safety pin are disclosed in Korean Registered Utility Model No. 20-0225763, titled "coupler for excavator", Korean Registered Patent No. 10-0397586, titled "safety device of clamp for mounting excavator bucket", and the like. However, in the case of using a safety pin, since a 2 driver or assistant worker of an excavator needs to directly insert or detach the safety pin into or from the safety-pin hole of a quick coupler, there is a disadvantage in that the work is onerous and difficult and much time is taken. In this manner, in the case of a quick coupler in the related art, since the safety pin needs to be manually engaged, the work is onerous and in many cases, because of the onerousness, the worker uses the quick coupler without engaging the safety pin, so that there is a problem in that safety accidents may occur with high possibility. In order solve the problem, Korean Registered Patent No. 10-1096085 discloses a "quick coupler for an excavator including an automatic safety device which is configured as a combination of an automatic locking cylinder and a hooking protrusion. However, since the safety device disclosed in the quick coupler for a quick coupler needs to be configured to include a hydraulic cylinder or the like, the safety device has disadvantages in terms of a structure. In addition, since the safety device still has the problems caused by disorder of a hydraulic cylinder, damage of a hydraulic hose, or the like, there is a disadvantage in that reliability of the safety device is low. By taking into consideration these points, Korean 3 Registered Patent No. 10-1210833, titled an "automatic safety device for a quick coupler" discloses a hitch which is automatically locked and released in cooperation with a moving hook operated by a hydraulic cylinder as a safety device. In other words, the above-described Patent Document discloses a safety device having a structure where the hitch is elastically supported by a coil-shaped spring which is erected on an upper surface of a front end portion of the hitch which is installed in a body. However, in the case where concrete demolition work or the like is performed by using the attachment such as a breaker, an external force is frequently exerted in the direction of lifting up the hitch. At this time, if the external force exerted to the hitch is higher than an elastic force of the spring, there is a problem in that the spring is compressed and the attachment pin is disassembled. On the other hand, International Patent Application Publication No. W02008/051095 (published on May 2, 2008) also discloses a "coupler" including an automatic safety device which is configured as a combination of an automatic locking cylinder and a hooking protrusion. However, in the coupler disclosed in the patent document, in order to hook first and second connection pins connecting an attachment to the coupler to first and second 4 docks formed at two sides of the coupler, respectively, a second element which is slid forward and backward by a hydraulic cylinder is moved to a first position (the state where the first dock is opened as illustrated in in Fig. 9A), a second position (the state where the first dock is closed by a first connection pin retaining means when the second element is moved backward as illustrated in Fig. 9C), and a third position (the state where the second connection pin is hooked with the second dock when the second element is moved forward). In other words, in order to hook and release the first and second connection pins which connect the attachment to the first and second docks of the coupler, the second element which is moved forward and backward by the hydraulic cylinder needs to be moved to the three different positions. Therefore, there is a problem in that much time is taken to perform an operation of coupling or disassembling the attachment. SUMMARY OF THE INVENTION The present invention is to provide an automatic safety device for a quick coupler, wherein the safety device is configured as a combination of new-forms of latches which are automatically latched or released in cooperation with a cylinder side which operates a moving 5 hook of the quick coupler for coupling or disassembling an attachment such as a bucket or a breaker, so that it is possible to secure worker's convenience and safety; even in the case where an external force is frequently exerted during works, it is possible to maintain a stable engagement state of an attachment pin and to prevent danger of safety accidents; and it is possible to speedily perform operations of coupling or disassembling the attachment. According to the present invention, there is provided an automatic safety device for the quick coupler. The automatic safety device for a quick coupler includes: a body which is linked and assembled with an arm and a link device of an excavator by using pin holes which are formed at front and rear sides thereof; a fixed hook which is formed at a lower portion of the rear side of the body; a cylinder which is supported by using a cylinder pin at a rear end portion thereof in a bottom of an inner side of the body; a slide-type moving hook which is disposed at a lower portion of the front side of the body to be connected to a rod of the cylinder by a hook pin and to hook or release an attachment pin; and a latch assembly which is configured as a combination of two latches which are disposed above the fixed hook at the rear side of the lower portion of the body and which are exerted with a force of a spring and are in contact with the moving hook 6 to be cooperatively operated, so that the two latches together with the fixed hook hooks or releases the attachment pin. Therefore, the automatic safety device for the quick coupler can maintain a stable engagement state of the attachment pin by using the latch assembly, so that even in the case where an external force generated during concrete demolition works is frequently exerted, it is possible to solve the problem of the diassembing of the attachment pin. Accordingly, it is possible to prevent danger of safety accidents. The latch assembly is configured to include a first latch which is rotatably supported by a latch pin at a rear end thereof to latch an upper portion of the attachment pin, a second latch which is rotatably supported by a cylinder pin at a middle portion thereof to be in contact with the moving hook side and in contact with the first latch side to press the first latch downward, and a round bar which is elastically supported by a spring at a rear end portion thereof and is moved forward and backward to allow a front end portion thereof to be in contact with a second latch side to push out the second latch. Herein, it is preferable that the first latch, the second latch, the round bar, the spring, and the like of the latch assembly are supported at the body unit side of 7 the cylinder, so that the first latch, the second latch, the round bar, the spring, and the like of the latch assembly together with the cylinder side constitute an assembly form. In addition, it is preferable that the second latch of the latch assembly is configured so that a rear surface of a lower end portion thereof which is in contact with the rear end portion of the moving hook is formed as an inclined surface and a rear surface of an upper end portion thereof which is in contact with the front end portion of the round bar is formed as a round surface, so that cooperative operations according to the contact are smoothly performed. In addition, it is preferable that, in the case where the moving hook is configured as a slide-type moving hook, the moving hook is straightly moved and guided along two slide grooves formed in the body by using slide protrusion portions formed at two sides thereof so as to hook or release the attachment pin. In an automatic safety device for the quick coupler according to the present invention, it is possible to obtain the following advantages. First, a safety device which is automatically locked and released in cooperation with a moving hook operated by a cylinder for coupling and disassembling an attachment is 8 employed, so that the safety device is convenient in use and it is possible to prevent damage to machinery and danger of safety accidents according to coupling and disassembling of the attachment. Second, a safety device which is configured as a combination of first and second latches which are cooperatively operated and a spring which is horizontally installed at the cylinder side is employed, so that, even in the case where an external force is frequently exerted during works, it is possible to secure a firm, stable engagement state of the attachment pin and to further improve safety. Third, the two latches, the spring, the round bar, and the like as components of the safety device are combined as an assembly form at the cylinder side, so that the structure is simple, and thus, it is possible to obtain advantageous effect in terms of treatment and maintenance. Fourth, the moving hook which is moved forward and backward by the cylinder is allowed to moved to two positions, that is, a first position (a state where the moving hook is opened) and a second position (a state where the fixed hook is closed by the hitch pin when the moving hook is moved forward and, at the same time, the other-side attachment pin is hooked with the moving hook), so that the attachment can be coupled or disassembled. Therefore, it 9 is possible to speedily perform operations of coupling the attachment with the coupler or disassembling the attachment from the coupler. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded perspective diagram illustrating a quick coupler with an automatic safety device according to an embodiment of the present invention. Fig. 2 is an assembled perspective diagram illustrating the quick coupler with the automatic safety device according to the embodiment of the present invention. Fig. 3 is an assembled perspective diagram illustrating the automatic safety device according to the embodiment of the present invention for the quick coupler. Fig. 4 is a perspective cross-sectional diagram illustrating the automatic safety device according to the embodiment of the present invention for the quick coupler. Fig. 5 is a cross-sectional diagram illustrating the automatic safety device according to the embodiment of the present invention for the quick coupler. Figs. 6 and 7 are cross-sectional diagrams illustrating operation states of the automatic safety device according to the embodiment of the present invention for the quick coupler. 10 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the attached drawings. Figs. 1 and 2 are perspective diagrams illustrating a quick coupler with an automatic safety device according to an embodiment of the present invention. Figs. 3 to Fig. 5 are perspective and cross-sectional diagrams illustrating the automatic safety device according to the embodiment of the present invention for the quick coupler. As illustrated in Figs. 1 to 5, the automatic safety device for the quick coupler is configured by combining a moving hook which is operated in a slide manner and a latch assembly which is operated in cooperation with the moving hook, so that the automatic safety device has a structure capable of automatically operates at the quick coupler engagement time and the using time with convenience at the engagement time and safety at the using time. In the automatic safety device, pin holes 10a and 10b for engagement with arm-side and link-device-side pins of an excavator are disposed at front and rear sides of an upper portion of the automatic safety device; and a body 11 where a fixed hook 12 for engagement with an attachment pin is integrally formed is disposed at a rear side of a lower portion of the automatic safety device. A predetermined space is formed in an inner portion of the body 11, and a cylinder 14, a slide-type moving hook 16, and the like which are described later are installed in the space. Two slide grooves (denoted by reference numeral 27 in Figs. 6 and 7) are formed on an inner wall of the body 11 to be parallel to the longitudinal direction of the body. In addition, slide protrusion portions 26 formed on two side surfaces of the moving hook 16 are inserted into the slide grooves 27 so as to be slidingly guided. In other words, at the straight moving time of the moving hook 16 for engagement with or for separation from the attachment pin, the moving hook 16 can be guided by the slide protrusion portions 26 which move along the slide grooves 27. In addition, a towing hook 30 which is formed in a plate shape traversing the body space in a width direction is disposed at the front side of the upper portion of the body 11. In this case, the towing hook 30 can be used for moving work pieces in the state where the quick coupler is mounted on the excavator and no attachment is attached. In addition, a cylinder 14, for example, a hydraulic cylinder which is operated in a hydraulic manner is arranged as an actuator means for operating the moving hook 16. The cylinder 14 is arranged to be parallel to the space formed in a bottom of an inner side of the body 11 12 and has a structure where a rod thereof is directed forward and a rear portion thereof is supported. For example, the cylinder 14 is installed in a structure where a rod thereof is disposed in a horizontal posture to be directed forward in the inner space of the body 11 and, in this state, a rear end of the cylinder body is engaged with the body 11 through a cylinder pin 13 so as to be supported by the cylinder pin 13 of the rear end portion thereof. In addition, the moving hook 16 together with the fixed hook 12 is arranged as a means for engaging an attachment pin. In this case, the moving hook 16 is installed in a structure where the moving hook 16 is disposed at the front side of the lower portion of the body 11 to be connected to the rod of the cylinder 14. Particularly, unlike a rotation-type moving hook installed in an existing quick coupler, the moving hook 16 is configured as a slide-type moving hook which is straightly moved along the forward-backward direction of the body. Due to the operation characteristics thereof, the moving hook 16 has an advantage in that the moving hook 16 can be applied to various types of attachments having different distances between attachment pins. The slide protrusion portions 26 are formed at the two side surfaces of the moving hook 16 to be parallel to 13 the longitudinal direction of the hook and to be protruded. The slide protrusion portions 26 are inserted into the slide grooves 27 in the body 11. Therefore, the moving hook 16 can be straightly guided by using the slide protrusion portions 26 which are inserted into the slide grooves 27 to be slid. A pair of pin engagement portions 31a is formed at the upper side of the front end portion of the moving hook 16. A pin engagement portion 31b formed in the rod of the cylinder is disposed between the pin engagement portions 31a, and the pin engagement portions 31a are engaged with each other by the hook pin 15. When the cylinder 14 performs forward and backward operations, the moving hook 16 is also slidingly operated forward and backward to hook or release the attachment pin. In addition, in the moving hook 16, an oil supply device 32 is installed as a means for supplying oil to a hook slide portion, that is, a frictional portion between the slide protrusion portions 26 and the slide grooves 27. The oil supply device 32 is installed at the front end portion of the moving hook 16. The oil injected through the oil supply device 32 is flown out from an oil hole (not shown) formed on a side surface of the slide protrusion portions 26 through an inner passage (not shown) of the moving hook to be supplied to a slide contact 14 portion. Due to the supplied oil, the straight slide movement of the moving hook 16 is more smoothly performed. In addition, the upper portion of the body 11 is covered with a cover 28. The cover 28 has a function of protecting the cylinder 14 and the like disposed inside thereof from external impact, extraneous materials, or the like. A latch assembly 18 is installed as a means for substantially performing a function of a safety device. The latch assembly 18 is configured so that the latch assembly 18 together with the fixed hook 12 latches or releases the attachment pin by using a combination of two latches which are cooperatively operated. Particularly, the latch assembly 18 is configured so as to maintain a stable engagement state of the attachment pin even in the case where an external force is exerted in upward and downward directions, for example, even in the case of concrete demolition work or the like. A first latch 20 is installed so as to be rotatably supported by a latch pin 19 which is engaged at the rear end thereof and to latch the upper portion of the attachment pin. The first latch 20 is configured in a rectangular plate shape to include a boss portion 20a which is formed at the rear end portion thereof for engagement with the latch pin 19 and a hook portion 20b which is 15 formed at the front end portion thereof to partially surround and hold the attachment pin. The first latch 20 is installed in a structure where the first latch 20 is disposed above the fixed hook 12 at the rear side of the lower portion of the body 11 to face the fixed hook 12 and is rotatably supported by the latch pin 19, which is engaged with the boss portion 20a of the rear end portion thereof, at the side of the body unit 23 of the cylinder 14. In other words, a horizontally-extending bar member is formed in the body unit 23 of the cylinder 14. In the state where the bar member is inserted into a cut portion of the boss portion 20a of the first latch 20, the boss portion side of the first latch 20 and the bar-member side of the body unit 23 are engaged with each other by the latch pin 19, so that the first latch 20 is rotated about the latch pin 19 to allow the hook portion 20b at the front end portion thereof to latch the attachment pin. In addition, the first latch 20 is rotated due to the contact with the moving hook 16, and thus, the hook portion 20b at the front end portion thereof is lifted up, so that the released state of the attachment pin (the opened state of the fixed hook) can be maintained. In other words, when the rear end portion of the first latch 20 is pressed by the moving hook 16 in the 16 state where the latching by the later-described second latch 21 is released, the hook portion 20b at the front end portion of the first latch 20 is lifted up, As a result, the fixed hook 12 is opened, so that the attachment pin can be released. Herein, in some structures of the quick coupler, the moving hook 16 may be difficult to be in contact with the first latch 20. In these structures, as a means for recovering the posture of the first latch 20, that is, a means for allowing the hook portion 20b of the first latch 20 to be lifted up, a return spring (not shown) may be installed above the latch pin engagement portion of the first latch 20. Therefore, in the state where the first latch 20 is not pressed by the second latch 21, the hook portion 20b of the first latch 20 is lifted up by the return spring. In addition, the second latch 21 is installed so that the second latch 21 is rotatably supported by the cylinder pin 13 engaged with a middle portion thereof to press the first latch 20 downward. The second latch 21 is configured in a substantially "E" shape. In the state where the second latch 21 is combined to the rear end portion of the body unit 23 of the cylinder 14, the second latch 21 is engaged by the cylinder pin 13, so that the second latch 21 can be rotated about 17 the cylinder pin 13. The lower end portion of the second latch 21 is in contact with the upper surface of the first latch 20, that is, the upper surface of the hook portion 20b and presses the hook portion 20b of the first latch 20 downward. In the case where the lower end portion of the second latch 21 is in contact with the moving hook 16, the second latch 21 maintains an inclined posture. In the case where the upper end portion of the second latch 21 is in contact with the later-described round bar 22, the second latch 21 maintains a vertically erected posture. In other words, due to the cooperative contact of the moving hook 16 and the round bar 22, in the case where the second latch 21 is in the erected posture, the first latch 20 can be pressed downward; and in the case where the second latch 21 is in the inclined posture, the force exerted to the first latch 20 can be released. For example, when the round bar 22 is moved forward, the upper end portion of the second latch 21 is pushed out, so that the second latch 21 is in the erected posture, and thus, the first latch 20 is pressed downward. When the moving hook 16 is moved backward, the lower end portion of the second latch 21 is pushed out, so that the second latch 21 is in the inclined posture, and thus, the first latch 20 is lifted up by the restoring force of the first latch 20 18 itself. In addition, the rear surface of the lower end portion of the second latch 21 is configured as an inclined surface 24 so as to maintain appropriate contact with the rear end portion of the moving hook 16, which is configured as a corresponding inclined surface. In addition, the rear surface of the upper end portion of the second latch 21 is also configured as a round surface 25 so as to maintain appropriate contact with the front end side of the round bar 22. The spring 17 and the round bar 22 are installed as a means for converting the posture of the second latch 21 to the erected posture. The round bar 22 is elastically supported by the spring 17 at the rear end thereof to be moved forward and backward so as to allow the front end portion thereof to push the rear surface of the upper end portion of the second latch 21. The spring 17 and the round bar 22 are installed in a horizontal posture within a slide hole 29 formed in the body unit 23 of the cylinder 14. The front end portion for the round bar 22 is exposed outward from the slide hole 29, so that the round bar 22 is always in contact with the second latch 21. Herein, it is preferable that two pairs of the spring 17 and the round bar 22 are installed at the left 19 and right sides so that the contact with the second latch 21 is maintained balanced. On the other hand, all the components constituting the latch assembly 18, that is, the first latch 20, the second latch 21, the spring 17, the round bar 22 are installed in the body unit 23 of the cylinder 14, so that an assembly form can be configured. For example, the first latch 20 is installed in a pin structure at the lower side of the body unit 23, and the second latch 21 is installed in a pin structure at the rear end side of the body unit 23. In addition, the spring 17 and the round bar 22 are installed to be retained in the inner side of the upper portion of the body unit 23. Therefore, the cylinder 14 including all the components constituting the latch assembly 18 is configured in an assembly form. Accordingly, it is possible to obtain an advantage of easily performing operations of assembling, checking, maintenance, and the like. The operation states of the automatic safety device for the quick coupler having the above-described configuration are as follows. Figs. 6 and 7 are cross-sectional diagrams illustrating a lock operation state and a release operation state in the automatic safety device according to the embodiment of the present invention for the quick coupler. 20 As illustrated in Figs. 6 and 7, first, the locked state where the moving hook 16, the fixed hook 12, and the latch assembly 18 of the quick coupler are engaged with the two attachment pins 100a and 100b is as follows. When the cylinder 14 is moved forward, the moving hook 16 is slid to the front side of the body 11 to hook the one-side attachment pin 100a. At the same time, in the state where the lower portion of the other-side attachment pin 100b is supported by the fixed hook 12, the second latch 21 is erected by the round bar 22 which is pushed out by the spring 17, and the first latch 20 is pressed by the lower end portion of the second latch 21. Therefore, the first latch 20 is inclinedt downward to allow the hook portion 20b at the front end portion thereof to latch the attachment pin 100b. In this manner, the one-side attachment pin 100a of the attachment is automatically engaged by the moving hook 16, and the other-side attachment pin 100b is automatically engaged by the first latch 20 and the fixed hook 12 as the upper and lower latches, so that the attachment such as a bucket can be easily attached to the quick coupler. Herein, the engagement process of the two attachment pins 100a and 100b of the attachment may include the step of hooking the lower side of the attachment pin 100b by the fixed hook 12 and the step of operating the cylinder 14 to 21 engage the moving hook 16 with the attachment pin 100a and engage the first latch 20, which is pressed and inclined downward by the spring force, with the upper side of the attachment pin 100b. In the case where the attachment pin 100b is engaged by the latch assembly 18 and the fixed hook 12, the attachment pin 100b is engaged by the combination structure of the horizontally-pushing round bar, the second latch which can maintain the erected posture due to the round bar, and the first latch which is pressed by the second latch in the erected posture. Therefore, even in the case where an external force is frequently exerted in the upward and downward directions, that is, in the direction of lifting up the first latch, for example, even in the case of concrete demolition work or the like, it is possible to maintain a stable engagement state of the attachment pin. Next, the released state of the attachment pin, that is, the opened state where he moving hook 16, the fixed hook 12, and the latch assembly 18 of the quick coupler are released from the two attachment pins 100a and 100b is as follows. When the cylinder 14 is moved backward, the moving hook 16 is slid to the rear side of the body 11 to be separated from the one-side attachment pin 100a (the attachment pin is released) Due to the contact with the 22 moving hook 16 which is moved backward, the lower end portion of the second latch 21 is pushed out, so that the second latch 21 is rotated counterclockwise. At the same time, when the cylinder 14 is returned (moved backward), the moving hook 16 is slid to the rear side of the fixed hook 16, the rear surface of the hook portion of the moving hook 16 which is moved backward, that is, the rear surface of the hook portion which hooks the attachment pin 100a is allowed to be in contact with the rear end portion of the first latch 20. Therefore, the rear end portion of the first latch 20 is pressed downward, so that the first latch 20 is rotated counterclockwise. Subsequently, the upper end portion of the second latch 21 rotating counterclockwise pushes the round bar 22 forward and is inclined. In addition, the hook portion 20b of the first latch 20 which is released from the second latch 21 is lifted up, so that the first latch 20 is separated from the other-side attachment pin 100b (the locking of the attachment is released). As a result, the attachment pin 100b is extracted through the separation gap between the first latch 20 and the fixed hook 12. Next, the attachment such as a bucket is detached from the quick coupler, and the work is finished. Otherwise, the attachment is replaced with another attachment, and the attachment is in the usable state. 23 In this manner, in the present invention, the two hook portions of the quick coupler are engaged with the attachment pins, and simultaneously, the safety device, that is, the latch assembly is automatically operated. Therefore, it is possible to solve problems in the worker's convenience and safety. In addition, since the slide-type moving hook is employed, it is possible to apply the moving hook to various standards of attachments without adjusting the distance between the hooks of the quick coupler (since the distance between the hooks of the quick coupler can be changed). Particularly, a combination of the horizontal-posed spring and round bar, the erected second latch, and the first latch pressed by the second latch is applied, so that in the case where concrete demolition work is performed by using the attachment such as a breaker, even in the condition where an external force is frequently exerted, it is possible to entirely solve the problem of the disassembling of the attachment pin and to improve the safety and efficiency of the work. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that the present invention is not limited thereto and various changes in form and details may be made therein 24 without departing from the spirit and scope of the present invention as defined by the appended claims. Description of Reference Numerals 10a, 10b: pin hole 11: body 12: fixed hook 13: cylinder pin 14: cylinder 15: hook pin 16: moving hook 17: spring 18: latch assembly 19: latch pin 20: first latch 21: second latch 22: round bar 23: body unit 24: inclined surface 25: round surface 26: slide protrusion portion 27: slide groove 28: cover 29: slide hole 30: towing hook 25 31a, 31b: pin engagement portion 32: oil supply device Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates. The reference numerals in the following claims do not in any way limit the scope of the respective claims. 26