Abstract:
A gas detector can be releasibly coupled to one of a group of elongated probes each of the probes includes a detector connecting end and a gas in flow/outflow end. The connecting end includes a helical attaching feature which when coupled to the detector defies a plurality of spaced apart angular locking positions. A locking position is selected in response to a flow of air in an adjacent duct to which the detector is being attached. Where the detector carries an elongated display device, the locking position can be selected so that the display device exhibits a desired presentation.

Description:
FIELD 
       [0001]    The application pertains to duct mountable ambient condition detectors. More particularly, the application pertains to such detectors which include detachable air sampling probes. 
       BACKGROUND 
       [0002]    Stand alone or system based duct mounted detectors find use in a variety of installations including ventilation and air conditioning ducts which provide fresh air to monitored regions. In such installations, it is useful to monitor concentrations of airborne gases, such as carbon dioxide. 
         [0003]    In such ducts, air can be moving in vertical or horizontal directions. Quite apart from the direction of air movement, it is, at times, desirable to orient the detectors, relative to the adjacent region, so that any display devices carried on the detector can be easily read by local personnel. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  illustrates an exemplary system in accordance herewith; 
           [0005]      FIG. 2A  is a view of one detector and associated probe in accordance herewith; 
           [0006]      FIG. 2B  is a view of another detector and associated probe in accordance herewith; 
           [0007]      FIG. 3A  is a probe side view of the detector and probe of  FIG. 1 ; 
           [0008]      FIG. 3B  is an enlargement of the view of  FIG. 3A  with the probe engaging the housing of the detector; 
           [0009]      FIG. 4  is an enlarged view of the detector and probe of  FIG. 3  where the probe has been locked to the detector with a vertical flow orientation; 
           [0010]      FIG. 5A  illustrates the probe of  FIG. 4  adjacent to the detector and before rotation; 
           [0011]      FIG. 5B  illustrates the probe of  FIG. 5A  adjacent to the detector and after rotation with a vertical flow orientation; 
           [0012]      FIG. 6A  illustrates the probe of  FIG. 2A  adjacent to the detector and before rotation thereof; 
           [0013]      FIG. 6B  illustrates the probe of  FIG. 6A  adjacent to the detector and after rotation with a horizontal flow orientation; 
           [0014]      FIG. 7  is a cross-section taken along plane  7 - 7  of  FIG. 9 ; 
           [0015]      FIG. 8  is a cross-section taken along plane  8 - 8  of  FIG. 9 ; and 
           [0016]      FIG. 9  is a cross-section illustrating additional aspects of the embodiment of  FIG. 2A . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    While disclosed embodiments can take many different forms, specific embodiments thereof are shown in the drawings and will be described herein in detail with the understanding that the present disclosure is to be considered as an exemplification of the principles thereof as well as the best mode of practicing same, and is not intended to limit the application or claims to the specific embodiment illustrated. 
         [0018]    In embodiments hereof, separate air sampling probes can be releasibly coupled to the detector&#39;s body. By selectively orienting the respective probe, inflow and outflow ports of the probe can be oriented to maximize air flowing into the probe and facilitate air flowing from the probe. At the same time, the housing to which the probe is coupled can be independently oriented to provide portrait orientation for a viewer of any display device carried by the housing. 
         [0019]    In one aspect, the probe can be formed as an elongated tube with two internal, substantially parallel, channels. One channel extends from a sampling end to a sensing end and provides inflowing air to a sensing region of the detector. A second, parallel, channel provides a parallel path between those ends for air flowing from the sensing region of the detector back into adjacent air flow. 
         [0020]    The sampling end can include one or more inflow ports and one or more outflow ports. The inflow and outflow ports are oriented one hundred eighty degrees apart from one another on the tube, relative to a central axis of the tube. One part of a multiple position twist-lock connector can be provided at the sensing end of the probe. The detector can carry a second part of the connector. The probe can be releasibly attached to the detector by the connector with the ports having a selected orientation relative to an air flow being sensed, and where a display on the detector can exhibit a selected orientation for a viewer. 
         [0021]    Advantageously, in accordance herewith, various sizes and shapes of probes can be provided. An installer can choose and use an appropriate probe given the characteristics of the ducts to which the detector is being attached. 
         [0022]      FIG. 1  illustrates a combination  10  which includes a gas detector  12  and a plurality of attachable probes  14 . The detector  12  includes a hollow housing  12   a  which carries a human readable display device  12   b.  The device  12   b  can visually present gas concentrations as well as detector status for maintenance personnel in the vicinity. The housing  12   a  and display  12   b  are illustrated with a portrait orientation for ease in viewing. 
         [0023]    As those of skill in the art will understand, the probe  14   a  . . .  14   n  of the plurality  14  can have different lengths, depending on the characteristics of the respective duct to which the unit is to be attached, or different gas ports adjacent to distal ends  16   a  . . .  16   n.  Proximal ends  18   a  . . .  18   n  all carry a common coupling element, discussed below, which can rotatably and releasibly mate with housing  12 . 
         [0024]      FIG. 2A  illustrates detector  12  mounted on a panel P of a heating or air conditioning duct through which ambient air is flowing in a vertical direction V. The probe  16   i  extends into the duct to sample the vertically flowing air. The detector  12  is attached to the panel P of the duct by a fastener  20 . 
         [0025]      FIG. 2B  illustrates a detector  12 - 1 , similar to the detector  12  but without the display  12   b.  The probe  14   i,  in  FIG. 2B  extends into the respective duct and is attached thereto by the fastener  20 . 
         [0026]    As illustrated in  FIGS. 3A , B the detector  12  has a rear panel  12   d  which closes the hollow housing  12 . An annular coupling element  24  is carried on the panel  12   d.  As illustrated in  FIGS. 3A , B the proximal end of the probe  14   i  slidably engages the element  24 . The element  24  carries internal helical protrusions  24   a  which rotatably engage matching external helical patterns, such as  26   a, b.    
         [0027]    As the probe  14   i  engages the connector element  24  while being rotated, in a direction  30  about a central axis A thereof, see  FIG. 5A , the helical protrusions  24   a  and  26   a, b  slidably and rotatably lock the housing  12  to the proximal end  18   i  of the probe  14   i.  A base region  24   b  of the connector element  24  is located adjacent to a sensing region  36  of the internal gas sensor  38  of the detector  12 . 
         [0028]    The distal ends, such as end  16   i  of each of the probes  14  are formed with ambient air, including gas or gases of interest, inflow/outflow ports such as  32   a, b  (best seen in  FIGS. 8 ,  9 ). The probe, such as  14   i,  forms an inflow channel  40   a,  an outflow channel  40   b.  The channels are separated by a divider  40   c  which extends along the axis of symmetry A. Ambient air, including the gas(s) of interest travel along channel  40   a  to the sensing region  36  and sensor  38 , and then exit the probe  12   i  along channel  40   b.    
         [0029]      FIGS. 7-9  are various cross-sections which illustrate additional aspects of the present apparatus. Control circuits  44  couple the display to the sensor  38  as would be understood by those of skill in the art. 
         [0030]    Because the connector elements  24   a  and  26   a  can be arranged to provide a plurality of different starting/ending points for the probe  14   i  a final position, see  FIG. 5B  can be provided consistent with a vertical flow, such as the flow V of  FIG. 2 . Alternately, a final position, see  FIG. 6B  can be provided consistent with a horizontal flow. 
         [0031]    In summary, a respective probe twists and locks to the rear of the enclosure, or housing, via a helix. The helix can be started in one of 4 locations. This option will allow the vent orientation to be vertical or horizontal. The tube also includes a divider. This divider is symmetrical and will permit the sample of duct air to travel to the housing, and sensor, and return to the duct at a constant velocity. The tube has the capability of slowing the speed of the incoming air. The tube completes a closed air circuit from the duct to the sensor and back via three seals. These include, a tube to the ambient room air seal implemented via an axial O-ring; a sensor board to inside the housing sea; and, the collar, carried on the housing for the detector, which prevents the room air from mixing with the duct air. 
         [0032]    From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope hereof. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims. Further, logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. Other steps may be provided, or steps may be eliminated, from the described flows, and other components may be add to, or removed from the described embodiments.