1. A security sensor system for detecting an object when the latter intercepts passage of a sensing beam, which system comprises:
a beam projecting unit including a beam projector for projecting the sensing beam and a drive circuit for driving the beam projector; and
a beam receiving unit including a beam receiver for receiving the sensing beam,
wherein the beam receiving unit also includes a received beam level detector for detecting a level of the sensing beam received, a level setting circuit for setting a proper range of the received beam level, a request signal output circuit for outputting a request signal requesting an adjustment of an amount of the sensing beam projected from the beam projector in the case that the received beam level departs from the proper range, and a transmitter for transmitting the request signal to the beam projecting unit; and
wherein the beam projecting unit also includes a beam projecting power adjustor operable in response to the request signal from the beam receiving unit to drive the drive circuit to thereby adjust an amount of the sensing beam, projected from the beam projector, so that the received beam level can fall within the proper range.
2. The security sensor system as claimed in claim 1, further comprising a proper range adjustor for adjusting the proper range with change in time of the received beam level.
3. The security sensor system as claimed in claim 2, wherein the proper range adjustor adjusts the proper range based on an average value of the received beam level every predetermined time width.
4. The security sensor system as claimed in claim 3, wherein the proper range adjustor includes an average value calculator for calculating the average value of the received beam level and a level width setting circuit for setting a predetermined level width, corresponding to the proper range, with the average value taken as a center value.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-39. (canceled)
40. A method of fixing a timber component to a composite panel incorporating a metal deck and a settable material cast on the deck, the method comprising the step of piercing nails having a profiled shank through the timber component and at least the metal deck of the composite panel.
41. A method according to claim 40, wherein the at least one timber component is a window or door fixture.
42. A method of fixing overlaying components together comprising the step of piercing nails having a profiled shank through the components to fix those components together, wherein the components form part of a composite panel incorporating a deck and a settable material cast on the deck, and the components being fixed together prior to casting of the settable material.
43. A method according to claim 42, wherein the nails have a serrated profile on their shank.
44. A method according to claim 42 wherein the nails are installed using gas powered nail gun.
45. A panel assembly for use in a composite panel, the assembly comprises a deck formed from a plurality of metal sheets, the sheets having opposite ends and opposite sides that extend between said ends, each sheet having an intermediate section and side margins that are turned out of the intermediate section and form stiffening formations that extend between the opposite ends, the side margins of adjacent sheets overlap and are fixed together by nails having profiled shanks that extend through the overlapping side margins, the panel assembly further comprising a peripheral edge that extends around the deck and which is formed from one or more side members, the deck and the edge forming a cavity arranged to receive a settable material cast on the deck to form the composite panel.
46. A panel assembly according to claim 45, wherein the one or more side members lap with the deck and are fixed to the deck by said nails having said profiled shanks
47. A panel assembly according to claim 45, wherein the deck incorporates an open region and at least one edge member is disposed at the open region, a first face of the edge member defining an edge of an opening in the resulting composite panel formed on casting the settable material on the deck, the edge member incorporating a base portion and an edge portion that upstands from the base portion, the upstanding edge portion incorporating the first face and the base portion laps the deck and is fixed to said deck by a plurality of said nails having profiled shanks, and wherein the side and edge members are formed of sheet metal.
48. A panel assembly according to claim 45, wherein the panel assembly further comprises one or more edge support members that interconnect the side andor edge members and the deck to support the edge member in accommodating hydrostatic forces on casting of the settable material on the deck.
49. A panel assembly according to claim 48, wherein at least one of the side support members is fixed to the deck by one or more said nails having profiled shanks
50. A panel assembly according to claim 45, wherein the nails have a serated profile on their shank.
51. A wall panel having a layer of hardened settable material and at least one opening containing a wall fixture, the opening being defined at least in part by at least one edge member that incorporates a first face that defines an edge of the opening and wherein the wall fixture is secured to said edge member at said first face by a plurality of nails having profiled shanks that extend through said edge member and said wall fixture.
52. A wall panel according to claim 51, wherein the hardened settable material abuts at least a portion of a second face of said edge member which is opposite said first face and said nails extend into said hardened settable material.
53. A wall panel according to claim 51, wherein the first face is profiled to include a rebate arranged to receive said wall fixture.
54. A wall panel according to claim 51, wherein said wall fixture is a window or door fixture.
55. A wall panel according to claim 51, wherein the nails have a serrated profile on their shank.
56. A wall panel according to claim 51, wherein the wall panel further comprises a panel assembly having a deck formed from a plurality of metal sheets, the sheets having opposite ends and opposite sides that extend between said ends, each sheet having an intermediate section and side margins that are turned out of the intermediate section and form stiffening formations that extend between the opposite ends, the side margins of adjacent sheets overlap and are fixed together by nails having profiled shanks that extend through the overlapping side margins, the panel assembly further having a peripheral edge that extends around the deck and which is formed from one or more side members, the deck and the edge forming a cavity arranged to receive a settable material cast on the deck to form the composite panel, with the hardened settable material overlaying the decking of the panel assembly.
57. A wall panel according to claim 56, wherein the hardened settable material is cementitious.
58. A wall panel according to claim 56, further comprising at least one region disposed behind said first face and having a material density less than the hardened settable material and which incorporates a leading end of said profiled nails therein.
59. A tilt-up wall panel for use in the construction of a building, the panel comprising a wall panel according to claim 12.