Abstract:
A hand piece for spraying powder is capable of grinding pellets and generating powder inside the hand piece. The hand piece includes: a pellet housing section for housing pellets; a powder generating section that grinds housed pellets and generates powder, and a spraying port that sprays the powder that has been generated in the powder generating section.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Stage Application of International Application No. PCT/JP2014/064778, filed on Jun. 3, 2014, which claims priority to Japanese Patent Applications No. 2013-118710, filed on Jun. 5, 2013, and No. 2014-015535, filed on Jan. 30, 2014. The entire disclosures of the above applications are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present invention relates to a hand piece used for spraying powder in dental treatment. 
         [0004]    2. Background Art 
         [0005]    In a conventional hand piece for spraying powder such as disclosed in Japanese Patent Publication No. 2001-293009, it was common that powder which had been powdered in advance was stored in a hand piece or an apparatus connected to a hand piece and the stored powder was sprayed from a spray port. 
         [0006]    However, in the conventional technique, since it is necessary to store medicine and the like to be sprayed which has been powdered in advance, there has been problems that a hand piece or an apparatus connected to the hand piece must have a storage part of sufficient capacity and that the device is inevitably enlarged. 
         [0007]    The present invention provides a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder. 
       SUMMARY OF THE INVENTION 
       [0008]    Specifically, the present invention provides the hand piece for spraying powder as follows. 
         [0009]    In the first embodiment, a hand piece for spraying powder including a pellet storage part for storing a pellet, a powder generation part for generating powder by grinding the stored pellet, and a spray port for spraying the powder generated in the powder generation part is provided. 
         [0010]    In the second embodiment, based on the first embodiment, the powder generation part includes an elastic body for urging the pellet in the pellet storage part, a grinder abutting on the pellet urged by the elastic body, and a vibrator for vibrating the grinder. 
         [0011]    In the third embodiment, based on the second embodiment, the powder generation part includes the elastic body for urging the pellet in the pellet storage part, the grinder abutting on the pellet urged by the elastic body, and a rotator for rotating the grinder. 
         [0012]    In the fourth embodiment, based on the second embodiment, the powder generation part includes a linear motion actuator for urging the pellet in the pellet storage part, a grinder abutting on the pellet urged by the linear motion actuator, and the vibrator for vibrating the grinder. 
         [0013]    In the fifth embodiment, based on the fourth embodiment, the powder generation part includes the linear motion actuator for urging the pellet in the pellet storage part, the grinder abutting on the pellet urged by the linear motion actuator, and the rotator for rotating the grinder. 
         [0014]    In the sixth embodiment, based on any one of the first embodiment to the fifth embodiment, the hand piece for spraying powder additionally has an acceleration gas pipe through which acceleration gas passes and a powder lead-out pipe that is connected between the powder generation part and the spray port for spraying powder by utilizing negative pressure generated by passing the acceleration gas through the acceleration gas pipe. 
         [0015]    In the seventh embodiment, based on any one of the first embodiment to the sixth embodiment, the pellet is obtained by compacting hydroxyapatite powder and wherein the spray port is for spraying the hydroxyapatite powder toward a human tooth. 
         [0016]    In the eighth embodiment, based on the sixth embodiment, the hand piece for spraying powder has a compressed gas cylinder for generating the acceleration gas and a power supply part for supplying power to the compressed gas cylinder and the powder generation part. 
         [0017]    In the ninth embodiment, based on the sixth embodiment, the hand piece for spraying powder has a gas (air) pump for generating the acceleration gas and a power supply part for supplying power to the gas pump and the powder generation part, is provided. 
         [0018]    By means of the foregoing, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a schematic view illustrating a structure of a hand piece for spraying powder according to embodiment 1. 
           [0020]      FIG. 2  is a schematic view illustrating a structure of a powder generation part in a hand piece for spraying powder according to embodiment 2. 
           [0021]      FIGS. 3A and 3B  are schematic views illustrating modes of a vibrator in the hand piece for spraying powder according to embodiment 2. 
           [0022]      FIGS. 4A and 4B  are schematic views illustrating modes of a rotator in a hand piece for spraying powder according to embodiment 3. 
           [0023]      FIG. 5  is a schematic view illustrating a structure of a hand piece for spraying powder according to embodiment 4. 
           [0024]      FIG. 6  is a schematic view illustrating a flow of powder and air in the hand piece for spraying powder according to embodiment 4. 
           [0025]      FIG. 7  is a schematic view illustrating another mode of the hand piece for spraying powder according to embodiment 4. 
           [0026]      FIG. 8  is a schematic view illustrating an example of a shape in the vicinity of a spray port in the hand piece for spraying powder according to embodiment 4. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Embodiments of the present invention will be described below by using the attached drawings. The present invention is not limited to these embodiments and can be put into practice in various modes within a range not departing from its gist. 
       Embodiment 1 
       [0028]    The hand piece for spraying powder of this embodiment is characterized in that powder generated by grinding a pellet inside the hand piece is sprayed from a spray port. 
         [0029]    The hand piece for spraying powder of this embodiment includes a pellet storage part, a powder generation part, and a spray port. Refer to  FIG. 1 .  FIG. 1  is a schematic view illustrating the structure of the hand piece for spraying powder of this embodiment. 
         [0030]    The “pellet storage part” ( 0101 ) is a part for storing a pellet ( 0102 ) which provides powder, having a function for fixing and keeping the pellet inside the hand piece. The pellet may be a compression body obtained by compressing powder, or a bulk body which is not made from powder. In the case where the pellet is a compression body, it has an advantage of being easier to grind than in the case where the pellet is a bulk body. 
         [0031]    As materials of the pellet, hydroxyapatite, white ceramics powder, colored ceramics powder, organic components, metal powder and the like can be used. Examples of the white ceramics include titanium oxide, aluminum oxide, zirconium oxide, silicon dioxide and the like. Examples of the colored ceramics powder include bismuth oxide and the like. Examples of the organic components include polyacrylic acid methyl powder, a polystyrene sphere, a nylon sphere and the like. 
         [0032]    The pellet storage part only needs to have enough capacity to store the pellet. Therefore, in the hand piece for spraying powder of this embodiment, unlike in the conventional technology where powder which has been powdered in advance is stored, powder can be sprayed even with a hand piece which does not have a powder storage part of enough capacity. 
         [0033]    The “powder generation part” ( 0103 ) is a part which is arranged closely to the pellet storage part, having a function for generating powder from the pellet. As specific configurations of the powder generation part, a configuration where a grindstone-shaped part grinds the pellet, a configuration where a brush powders the pellet by vibration, a configuration where a net-shaped part generates powder by grinding the pellet, a configuration where a propeller-shaped part powders the pellet by rotation and the like can be used. 
         [0034]    The “spray port” ( 0104 ) is a part which is connected to the powder generation part, having a function for spraying powder generated in the powder generation part. The shape of the spray port is not limited but is preferably circular in manufacturing. It may also be oval so that a spray area can be wide. 
         [0035]    The hand piece for spraying powder of this embodiment, in addition to the above components, has an actuator for generating powder ( 0105 ) for actuating the powder generation part and a power source ( 0106 ) of the actuator for generating powder. The actuator for generating powder actuates the powder generation part utilizing energy supplied from the power source. Then, powder is generated from the pellet by action of the powder generation part. 
         [0036]    The hand piece for spraying powder of this embodiment, in addition to the above components, has a compressed gas cylinder or a gas pump ( 0107 ) which supplies gas for making powder flow and a powder flow passage ( 0108 ) via which the powder generation part leads to the spray port. Powder generated in the powder generation part is carried to the powder flow passage by a flow of gas supplied from the compressed gas cylinder or the gas pump (which is called supplied gas) passes through the powder flow passage, and is sprayed from the spray port. Various kinds of gas such as air generated by the gas pump, air sealed in the compressed gas cylinder, nitrogen gas, helium gas and the like can be used. 
         [0037]    The hand piece for spraying powder of this embodiment can be used toward not only a human tooth but also various objects such as an implant body, bone, glass, a nail, an artificial joint and the like. The hand piece for spraying powder of this embodiment can also be used for wiring on printed boards, spraying conductors and metal powder and the like. In the case where the hand piece for spraying powder of this embodiment is used for purposes other than dental treatment, each of the above components is not limited in size and can be formed in any size. 
         [0038]    By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
       Embodiment 2 
       [0039]    The hand piece for spraying powder of this embodiment is characterized by being configured so that the powder generation part grinds the pellet urged by an elastic body by vibration of a grinder abutting on the pellet. The hand piece for spraying powder in which urging the pellet is performed by a linear motion actuator instead of the elastic body will also be described. 
         [0040]    The hand piece for spraying powder of this embodiment includes the pellet storage part, the powder generation part, and the spray port. Since the pellet storage part and the spray port are the same as described in embodiment 1, the description thereof is omitted. The powder generation part in this embodiment includes an elastic body, a grinder, and a vibrator. Refer to  FIG. 2 .  FIG. 2  is a schematic view illustrating the structure of the powder generation part in the hand piece for spraying powder of this embodiment. 
         [0041]    The “elastic body” ( 0209 ) is a part with elasticity, having a function of urging the pellet stored in the pellet storage part. An example of the elastic body in this embodiment includes a spring. As the pellet is urged by the elastic body, it is strongly pressed onto the grinder which will be described in detail, thereby grinding efficiency is improved. 
         [0042]    It may also be configured so that the pellet is urged by a linear motion actuator. The linear motion actuator is a machine element which converts input energy into linear motion. The linear motion means linear expanding and contracting motion or linear bending and stretching motion. Examples of the linear motion actuator include an air cylinder, an electric cylinder and the like. The air cylinder is a machine element which makes a piston move linearly by compressed air. This air cylinder urges the pellet by imparting pressure. The electric cylinder converts rotary motion of an electric motor into linear motion of a piston and the like. A hydraulic cylinder can also be used. The arrangement position of these linear motion actuators is the same as that of the elastic body. They may be arranged at a position where they can urge the pellet so that it abuts on the grinder. The type of linear motion actuator is not particularly limited, but it is preferable to be a small one. 
         [0043]    The “grinder” ( 0210 ) is a part abutting on the pellet, having a function for grinding the pellet to generate powder. As specific examples of the grinder, a grindstone, a brush, a net, a cutting blade and the like can be used. 
         [0044]    The “vibrator” ( 0211 ) is a part interlocking with the grinder, having a function for vibrating the grinder. An example of the vibrator includes an ultrasonic vibrator. For example, when the ultrasonic vibrator vibrates under conditions where the amplitude is around 10 micrometers and the frequency is 65 kilohertz, the grinder vibrates in interlock with the ultrasonic vibrator and the pellet is ground by vibration of the grinder. 
         [0045]    The vibrator may also be embodied by a motor. In this case, the motor can vibrate the grinder with an action having an amplitude that is larger than in the case where the ultrasonic vibrator is used. Whether to use the ultrasonic vibrator or the motor as the vibrator may be suitably determined according to material, structure, and composition of the pellet to be ground and the desired diameter (particle size) of powder. 
         [0046]    Schematic views of modes where the vibrator is embodied by the motor are illustrated in  FIGS. 3A and 3B .  FIG. 3A  is a schematic view illustrating a mode where the motor makes the grinder reciprocate (move longitudinally). As illustrated, the grinder ( 0301 ) is reciprocated (moved longitudinally) by the motor ( 0302 ), thereby the pellet ( 0303 ) urged against the grinder is ground.  FIG. 3B  is a schematic view illustrating a mode where the grinder is moved vertically by the motor. As illustrated, the grinder ( 0301 ) is moved vertically by the motor ( 0302 ), thereby the pellet ( 0303 ) urged against the grinder is ground. 
         [0047]    The positional relationship between the elastic body or the linear motion actuator for urging the pellet and the grinder is not limited to such a relationship that the grinder is arranged at the spray port side and the elastic body is arranged to face the grinder across the pellet, as illustrated in  FIG. 2 . That is to say, it may also be configured so that the elastic body or the linear motion actuator is arranged at the spray port side and the grinder is arranged to face the elastic body or the linear motion actuator across the pellet. The arrangement of the elastic body or the linear motion actuator and the grinder can be suitably determined according to the position of the pellet storage part and a storage opening for storing the pellet in the pellet storage part. It is desirable to determine the arrangement of each part considering ease of storing the pellet and the like. 
         [0048]    In configuring the powder generation part in this embodiment, the particle size of the generated powder can be changed by controlling a frequency, a cutting amount, and a feeding amount. The generation amount of the powder per unit time can also be changed by controlling a frequency or duty ratio. 
         [0049]    By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
       Embodiment 3 
       [0050]    The hand piece for spraying powder of this embodiment is characterized in that it is configured so that the powder generation part grinds the pellet urged by the elastic body by rotation of the grinder abutting on the pellet. 
         [0051]    The hand piece for spraying powder of this embodiment includes the pellet storage part, the powder generation part, and the spray port. Since the pellet storage part and the spray port are the same as described in embodiment 1, the description thereof is omitted. The powder generation part is the same as described in embodiment 2, except for the following points. 
         [0052]    The “powder generation part” of the hand piece for spraying powder of this embodiment includes the elastic body, the grinder, and a rotator. The “rotator” is a part interlocking with the grinder, and having a function for rotating the grinder. The motor can be used to embody the rotator, for example. 
         [0053]      FIGS. 4A and 4B  are schematic views illustrating modes where the grinder is rotated by the motor.  FIG. 4A  is a mode where the grinder is rotated in one direction continuously. As illustrated, the grinder ( 0401 ) is rotated in one direction by the motor ( 0402 ), thereby the urged pellet ( 0403 ) is ground.  FIG. 4B  is a schematic view illustrating a mode where the grinder alternately repeats clockwise rotation and counterclockwise rotation. As illustrated, the grinder ( 0401 ) alternately repeats clockwise rotation and counterclockwise rotation by action of the motor ( 0402 ), thereby the urged pellet ( 0403 ) is ground. 
         [0054]    By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
       Embodiment 4 
       [0055]    The hand piece for spraying powder of this embodiment is characterized by spraying powder utilizing negative pressure generated by acceleration gas. 
         [0056]    The hand piece for spraying powder of this embodiment includes the pellet storage part, the powder generation part, and the spray port, having an acceleration gas pipe and a powder lead-out pipe. Since the pellet storage part, the powder generation part, and the spray port are the same as described in embodiment 1, the description thereof is omitted. Refer to  FIG. 5 .  FIG. 5  is a schematic view illustrating the structure of the hand piece for spraying powder of this embodiment. 
         [0057]    The “acceleration gas pipe” ( 0512 ) is a part which acceleration gas passes through. The acceleration gas is gas supplied from an acceleration gas intake port ( 0513 ), and has a function for accelerating powder toward the direction of the spray port. The “powder lead-out pipe” ( 0514 ) is a part connected to the spray port, and has a function for carrying powder to the spray port. Besides atmospheric gas, various kinds of gas such as nitrogen gas, helium gas and the like can be used as the acceleration gas. A gas pump and a compressed gas cylinder filled with various kinds of gas can be used to supply the acceleration gas, for example. 
         [0058]    The hand piece for spraying powder of this embodiment, in addition to the above components, has an actuator for generating powder for actuating the powder generation part, a power source of the actuator for generating powder, a powder flow passage, and supplied gas ( 0515 ). 
         [0059]    Refer to  FIG. 6 .  FIG. 6  is a schematic view illustrating a flow of powder and air in the hand piece for spraying powder of this embodiment. First, the acceleration gas supplied from the acceleration gas intake port flows into the powder lead-out pipe. Since the powder lead-out pipe is joined with the powder flow passage, air inside the powder flow passage is pulled by the acceleration gas and negative pressure is generated in the powder flow passage and the powder generation part. Then, the powder generated in the powder generation part moves in the direction of the powder lead-out pipe, passes through the powder lead-out pipe, and is sprayed from the spray port. In this way, since powder is carried by negative pressure, an effect of powder being hard to adhere to a pipe wall can be obtained. 
         [0060]      FIG. 7  is a schematic view illustrating another mode of the hand piece for spraying powder of this embodiment. As illustrated, the hand piece for spraying powder has a gas pump ( 0707 ), by which air is taken in from an air intake port ( 0716 ), the acceleration gas is supplied to the acceleration gas pipe ( 0712 ), and supplied gas is supplied to the powder flow passage ( 0708 ) via the powder generation part ( 0703 ). The powder flows in the direction of the powder lead-out pipe ( 0714 ) by a flow of the supplied gas and negative pressure generated by the acceleration gas and is sprayed from the spray port ( 0704 ) after passing through the powder lead-out pipe. The gas pump in this mode may be replaced with a compressed gas cylinder. 
         [0061]      FIG. 8  is a view illustrating an example of the shape in the vicinity of the spray port in the hand piece for spraying powder of this embodiment . The shape in the vicinity of the spray port is not limited as long as it is suitable for spraying powder, but it is preferable to be formed as illustrated in  FIG. 8 . In the case where the hand piece for spraying powder of this embodiment is used in dental treatment, it is preferable to set the angle α to be 45° to 90°, and it is the most preferable to set the angle a to be 60° to 90°. 
         [0062]    In the hand piece for spraying powder of this embodiment, the ground powder is smoothly carried from the powder generation part to the spray port by action of negative pressure, and powder can be sprayed continuously and effectively. By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
       Embodiment 5 
       [0063]    The hand piece for spraying powder in this embodiment is characterized by being used for spraying powder generated by grinding a pellet obtained by compacting hydroxyapatite powder toward a human tooth for the purpose of dental treatment. 
         [0064]    The hand piece for spraying powder of this embodiment includes the pellet storage part, the powder generation part, and the spray port. Since the powder generation part is the same as described in embodiment 1, the description thereof is omitted. The pellet storage part and the spray port are the same as described in embodiment 1, except for the following points. 
         [0065]    The “pellet storage part” of the hand piece for spraying powder of this embodiment is characterized by storing a pellet obtained by compacting hydroxyapatite powder. “Hydroxyapatite” is a kind of calcium phosphate and is used for medicine, dental material, toothpaste, cosmetics and the like because of its high biocompatibility. 
         [0066]    The “spray port” of the hand piece for spraying powder of this embodiment is characterized by being used for spraying the hydroxyapatite powder toward a human tooth. For example, a user spray the hydroxyapatite powder generated in the powder generation part toward a tooth of a person to be treated for repair and recalcification of enamel or plaque removing in dental treatment. 
         [0067]    In the hand piece for spraying powder of this embodiment, all of the spray port, the acceleration gas pipe, and the powder lead-out pipe are preferably formed so that the diameter is in the range of from 0.1 mm to 30 mm. It is the most preferable that the diameter is in the range of from 0.5 mm to 10 mm. 
         [0068]    By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder can be provided. 
       Embodiment 6 
       [0069]    The hand piece for spraying powder of this embodiment is characterized by being used in a completely cordless manner since it has a compressed gas cylinder and a power supply part. 
         [0070]    The hand piece for spraying powder of this embodiment includes the pellet storage part, the powder generation part, and the spray port, having a compressed gas cylinder or a gas pump and a power supply part. Since the pellet storage part, the powder generation part, and the spray port are the same as described in embodiment  1 , the description thereof is omitted. 
         [0071]    The “compressed gas cylinder” is a part filled with gas, having a function for artificially producing a flow of air by jetting gas to generate the acceleration gas. The “gas pump” has a function for imparting kinetic energy to gas to generate the acceleration gas. The impeller type, the diaphragm type, the piston type and the like are specific methods for the gas pump. 
         [0072]    The “power supply part” is a part which supplies power needed for the compressed gas cylinder and the powder generation part to operate. Specifically, a lithium battery and the like can be used. The power supply part may be configured to supply power needed for the vibrator, the rotator, the linear motion actuator and the like to operate. 
         [0073]    By means of the present embodiment, a small and portable hand piece for spraying powder inside which a pellet is ground to generate the powder, which can be used in a completely cordless manner, can be provided. 
         [0074]    The hand piece used for spraying the powder being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be apparent to one of ordinary skill in the art are intended to be included within the scope of the following claims.