Patent Publication Number: US-2004059233-A1

Title: Inflation bulb for sphygmomanometer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001] This application claims the priority benefit of Taiwan application serial no. 91214877, filed Sep. 20, 2002.  
       BACKGROUND OF INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The invention relates generally to an inflation bulb for sphygmomanometer and, more specifically, to an inflation bulb that may be formed in a single body without the need of additional valve assembly.  
       [0004] 2. Description of the Related Art  
       [0005] Current sphygmomanometers are usually distinguished in different types including automatic electric sphygmomanometers, semi-automatic electric sphygmomanometers, and mercury type sphygmomanometers. The semi-automatic electric sphygmomanometer and the mercury type sphygmomanometer conventionally need the use of an inflation bulb. By repeated press and release of the inflation bulb, air gas is manually delivered to inflate the cuff of the sphygmomanometer.  
       [0006]FIG. 1A and FIG. 1B are respectively longitudinal and transversal views particularly illustrating an inflation bulb for sphygmomanometer known in the prior art. The inflation bulb  100  is internally hollow, and terminates in a gas inlet end  110  and a gas outlet end  120 . The gas inlet end  110  is provided with a gas inlet opening  112  that includes a unidirectional gas valve  130 . The gas outlet end  120  is further provided with a gas outlet opening  122  connected to a gas intake pipe  10 . Conventionally, the gas intake pipe  10  further connects to a gas reverse-flow preventing device (not shown). The unidirectional gas valve  130  is constructed from a main body  132 , the hollow interior of which mounts a sealing ball  134 . Two opposite ends of the valve  130  are respectively provided with through holes  136 ,  138 . The through hole  136  has a diameter larger than that of the sealing ball, and is provided with abutment fingers  140  that protrude at spaced intervals from one another at an edge of the through hole  136  to limit the move of the sealing ball within the main body  132 . The through hole  138  has a diameter smaller than that of the sealing ball  134 .  
       [0007] When the inflation bulb  100  is not pressed and is in its initial state, exterior air penetrates the inflation bulb  100  via the communicating hole  136  of the valve  130 , having a diameter larger than that of the sealing ball  134 .  
       [0008]FIG. 1C and FIG. 1D are respectively longitudinal and transversal views illustrating a pressed state of the inflation bulb known in the prior art. When the inflation bulb  100  is pressed, the air gas therein flows toward the two ends of the inflation bulb  100 . At the gas inlet end  110 , the air gas enters the valve  130  and pushes the sealing ball  134  to occlude the through hole  138 . The air gas therefore exits the inflation bulb  100  via the gas outlet opening  122 . By repeated press and release of the inflation bulb  100 , air gas is therefore delivered through the gas intake pipe  10  to inflate the cuff of the sphygmomanometer.  
       [0009] One disadvantage of the above structure is that the inflation bulb and the gas valve are distinct elements and therefore they have to be assembled with each other. This results in the increase of both fabrication cost and fabrication time. Furthermore, since the gas valve is usually made of a metallic material, the contact between the sealing ball and the through hole may be ineffective to achieve a hermetic sealing, which adversely lowers the yield of the inflation bulb.  
       SUMMARY OF INVENTION  
       [0010] An aspect of the invention is therefore to provide an inflation bulb that includes a lip structure formed in a single body with the inflation bulb to replace the conventional gas valve.  
       [0011] To accomplish the above and other objectives, the invention provides an inflation bulb that is suitable for use with sphygmomanometer, which may be a semiautomatic electric sphygmomanometer or a mercury type sphygmomanometer. The inflation bulb is internally hollow, and comprises a gas inlet end and a gas outlet end. An inner side of the gas inlet end forms inwardly protruding lips that are approximately flat. The lips define a gas inlet opening through which exterior air gas is allowed to penetrate the inflation bulb, the lips capable of occluding and opening the gas inlet opening. The gas outlet end includes a gas outlet opening. The gas outlet opening is further connected to a gas intake pipe.  
       [0012] According to other embodiments of the invention, the gas inlet opening may include various shapes such as a bar opening, a cross-shaped opening, or an Y-shaped opening. When the inflation bulb is pressed, the lips occlude the gas inlet opening, which forces the air gas inside the inflation bulb to flow out through the gas outlet opening to the gas intake pipe. When the operator releases the pressing action, the inflation bulb recovers its initial state to have the lips open the gas inlet opening, and therefore air flows into the bulb. By repeated press and release of the inflation bulb, air gas is thereby delivered through the gas intake pipe to inflate a cuff of the sphygmomanometer.  
       [0013] According to a preferred embodiment of the invention, an outer wall of the gas inlet end is further provided with a reinforcement portion that is approximately annular around the lips. The reinforcement portion is formed preferably by increasing the thickness of the outer wall of the gas inlet end for locally increasing its hardness. The operator is thereby prevented from pressing the inflation bulb at the location of the gas inlet end. The reinforcement portion also enables it to prevent an inadequate deviation of the lips, which may disable the occlusion of the gas inlet opening.  
       [0014] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. 
     
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
     [0015] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,  
     [0016]FIG. 1A and FIG. 1B are respectively longitudinal and transversal views illustrating an initial state of an inflation bulb for sphygmomanometer known in the prior art;  
     [0017]FIG. 1C and FIG. 1D are respectively longitudinal and transversal views illustrating a pressed state of an inflation bulb for sphygmomanometer known in the prior art;  
     [0018]FIG. 2A and FIG. 2B are respectively longitudinal and transversal views illustrating an initial state of an inflation bulb for sphygmomanometer according to an embodiment of the invention;  
     [0019]FIG. 2C and FIG. 2D are respectively longitudinal and transversal views illustrating a pressed state of an inflation bulb for sphygmomanometer according to an embodiment of the invention;  
     [0020]FIG. 2E and FIG. 2F are respectively longitudinal and transversal views illustrating a recovering state of an inflation bulb for sphygmomanometer according to an embodiment of the invention; and  
     [0021]FIG. 3A and FIG. 3B are transversal views illustrating different variations of an inflation bulb according to the invention. 
    
    
     DETAILED DESCRIPTION  
     [0022] The following detailed description of the embodiments and examples of the present invention with reference to the accompanying drawings is only illustrative and not limiting. Furthermore, wherever possible in the description, the same reference symbols will refer to similar elements and parts unless otherwise illustrated in the drawings.  
     [0023] Reference now is made to FIG. 2A and FIG. 2B to describe an inflation bulb according to an embodiment of the invention. As illustrated, an inflation bulb  200  is inwardly hollow, and includes a gas inlet end  210  and a gas outlet end  220 . An inner side of the gas inlet end  210  forms a pair of protruding lips  212  that are approximately flat longitudinally. The lips  212  form a gas inlet opening  214 . The gas inlet opening  214  includes, but is not limited to, for example, a bar-shaped opening. In an initial state of the inflation bulb  200 , the lips  212  occlude the gas inlet opening  214 . The gas outlet end  220  is opened with a gas outlet opening  222  that is connected to a gas intake pipe  10 . The gas intake pipe  10  is further connected to a gas reverse-flow preventing device (not shown), as it is conventionally known in the art. It should be noticed that the lips  212  are formed in a single body with the bulb  200 . The lips  212  and the bulb  200  may be made of, for example but no limited to, flexible rubber. The gas inlet end  210  has an outer wall provided with a reinforcement portion  216 . The reinforcement portion  216  appears generally annular around the lips  212 .  
     [0024]FIG. 2C and FIG. 2D are respectively longitudinal and transversal views illustrating a pressed state of the inflation bulb according to an embodiment of the invention.  
     [0025] When the inflation bulb  200  is pressed, the lips  212  occlude the gas inlet opening  214 . Due to the pressing force, the air gas within the inflation bulb  200 , blocked at the occluded gas inlet opening  214 , is compelled to exit through the gas outlet end  220 .  
     [0026]FIG. 2E and FIG. 2F are respectively longitudinal and transversal views illustrating a recovering state of the inflation bulb according to an embodiment of the invention.  
     [0027] By its own characteristic, the inflation bulb  200  is capable of recovering its initial state when the operator releases the pressing action. While the inflation bulb  200  is recovering its initial state, the lips  212  open the gas inlet opening  214 , which allows exterior air gas to penetrate the inflation bulb  200 . Through the repeated press/release actions as described above, air gas is therefore progressively delivered through the gas intake pipe  10 .  
     [0028]FIG. 3A and FIG. 3B are schematic views illustrating variant embodiments of the invention wherein the gas inlet opening  214  may include various adequate shapes such as a cross shape or an “Y” shape. Regardless of its shape, the gas inlet opening  214  is characterized in that it is opened when the inflation bulb  200  is recovering the initial configuration, and is occluded when the inflation bulb  200  is either in its initial configuration or pressed by the operator.  
     [0029] As described above, the reinforcement portion  216  is formed by, for example, increasing the thickness of the outer wall of the gas inlet end  210 , which locally increases its hardness. The operator is thereby prevented from pressing the inflation bulb  200  at the location of the gas inlet end  210 . The reinforcement portion  216  also prevents an inadequate deviation of the lips  212  from adversely occluding the gas inlet opening  214 .  
     [0030] As described above, the invention includes at least the following advantages.  
     [0031] (1) The lip structure and the inflation bulb are manufactured in one step, and the lip structure has the same function as the unidirectional gas valve of the prior art. The mount of the unidirectional gas valve therefore is unnecessary, and the fabrication cost and fabrication time are reduced.  
     [0032] (2) The flexible rubber material enables an effective occlusion of the gas inlet opening without gas leakage, which improves the yield of the inflation bulb.  
     [0033] It should be apparent to those skilled in the art that other structures that are obtained from various modifications and variations of different parts of the above-described structures of the invention would be possible without departing from the scope and spirit of the invention as illustrated herein. Therefore, the above description of embodiments and examples only illustrates specific ways of making and performing the invention that, consequently, should cover variations and modifications thereof, provided they fall within the inventive concepts as defined in the following claims.