Air blow gun

Abstract

In the present invention, an air blow gun 10 has: a main case 11 provided with a discharge nozzle 14; a unit accommodating chamber 29 that detachably accommodates a pulse blow unit 31 that intermittently outputs, to an intermittent output end part 39, air fed to an intermittent input end part 34, and detachably accommodates a continuous blow unit that continuously outputs, to a continuous output end part, air fed to a continuous input end part; a unit exchange lid by which the unit accommodating chamber 29 is opened or closed; and a manual valve 21 that is switched, by means of a trigger lever 24, between an open state in which air discharged from the pulse blow unit 31 or the continuous blow unit is discharged to a discharge nozzle 14, or a closed state in which the discharging is stopped.

Description

Technical Field

[0001] The present invention relates to an air blower that functions as both a continuous blower that continuously discharges air toward an object and a pulse blower that discharges air intermittently.

Background Art

[0002] An air blower is used to blow compressed air onto an object such as a workpiece or a painted surface to remove chips, dust, etc. on the surface of the object. There are a continuous blower that continuously discharges air toward an object and a pulse blower that discharges air intermittently. Patent Document 1 discloses an intermittent air blower, that is, a pulse blower that intermittently discharges air toward an object.

[0003] As described in Patent Document 1, a pulse blower has a switching valve for switching compressed air supplied from the outside into intermittent air, that is, pulsed air. The switching valve is also called a pulse blow unit. The switching valve that constitutes the pulse blow unit has a spool-type main valve, a small-diameter piston is provided at one end of the main valve, and a large-diameter piston is provided at the other end of the main valve. Each piston is incorporated into a pilot chamber inside the valve housing, and air is intermittently discharged from the switching valve due to a change in the thrust applied to both pistons.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Such pulse blow guns have a throttle valve that changes the flow rate of air flowing into the pilot chamber in order to change the pulse interval, but they cannot continuously discharge air. To continuously discharge air onto an object, a continuous blow gun must be used. In other words, if both pulse blow and continuous blow functions are required, two air blow guns must be prepared. On the other hand, considering the ease of operation for the operator, it is desirable for the shape of the continuous blow gun and pulse blow gun to be the same.

[0006] The objective of the present invention is to provide an air blow gun that functions as both a continuous blow gun and a pulse blow gun without changing the shape of the air blow gun. [Means for solving the problem]

[0007] The air blow gun of the present invention comprises a main body case provided with an air discharge nozzle, a unit housing chamber formed in the main body case to selectively house either a pulse blow unit that intermittently outputs air supplied from the outside to an intermittent input end to an intermittent output end, or a continuous blow unit that continuously outputs air supplied from the outside to a continuous input end to a continuous output end, a unit replacement lid provided in the main body case for opening and closing the unit housing chamber, and a manual valve provided inside the main body case that can be switched by a trigger lever between an open state for discharging air discharged from the pulse blow unit or the continuous blow unit to the discharge nozzle and a closed state for stopping discharge, and can be applied to either a continuous blow gun that continuously discharges air toward an object or a pulse blow gun that discharges air intermittently. [Effects of the Invention]

[0008] The main unit case is equipped with a unit housing chamber that can accommodate either a pulse blow unit or a continuous blow unit. When the pulse blow unit is placed in the unit housing chamber, pulsed air can be blown onto the target object. On the other hand, when the continuous blow unit is placed, air can be blown onto the target object continuously. In this way, by changing the unit depending on the type of air being blown onto the target object, a single air blow gun can be switched between the functions of a pulse blow gun and a continuous blow gun without changing the shape of the air blow gun. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view showing the appearance of an air blow gun, one embodiment of the design, as seen from the front and right side. [Figure 2] This is a side view showing the left side of the air blow gun. [Figure 3] This is a perspective view showing the unit conversion cover on the right side of the air blow gun in the open position. [Figure 4] This is a partially cutaway side view showing the inside of an air blow gun with a pulse blow unit installed. [Figure 5] This is a partially cutaway side view showing the inside of an air blow gun with a continuous blow unit installed. [Figure 6] These are pneumatic circuit diagrams for an air blow gun. (A) shows the case where a pulse blow unit is attached to the air blow gun, and (B) shows the case where a continuous blow unit is attached to the air blow gun. [Figure 7] This is a pneumatic circuit diagram showing the operation of the air blow gun when a pulse blow unit is installed. (A) shows the state when no air is supplied to the air blow gun from the outside, (B) shows the state immediately after air is supplied from the outside, (C) shows the state when the manual valve is operated and air is discharged from the nozzle, and (D) shows the state when air has been discharged from the nozzle for a predetermined time and the discharge of air has stopped. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will now be described in detail based on the drawings. As shown in Figures 1 and 2, the air blow gun 10 has a main body case 11 as the gun body, and the main body case 11 is assembled by joining two case halves 11a and 11b. Inside the main body case 11, there is a space for housing the equipment that constitutes the air blow gun. The main body case 11 has a grip portion 12 that can be held by an operator with one hand, and a nozzle holding portion 13 at the upper end of the grip portion 12 in Figure 1, and a discharge nozzle 14 made of conductive material is provided on the nozzle holding portion 13 of the main body case 11, protruding from the front of the main body case 11. The side of the main body case 11 on which the discharge nozzle 14 is provided is considered the front.

[0011] As shown in Figure 4, the discharge nozzle 14 is mounted on a nozzle holder 15 made of insulating material, which is located inside the tip of the main body case 11. An air outlet 16 made of conductive material is attached to the discharge nozzle 14, and a discharge hole 17 formed in the air outlet 16 communicates with a discharge channel 18 formed in the discharge nozzle 14. As shown in Figure 5, the central axis of the discharge nozzle 14 is inclined with respect to the front at an angle θ with respect to the longitudinal central axis of the main body case 11. The angle θ is approximately 105 to 110 degrees.

[0012] A manual valve 21 is mounted inside the main body case 11, adjacent to the nozzle holder 15. The manual valve 21 is a two-port, two-position directional control valve, and has a main valve mounted in the valve housing 22 so as to be reciprocally movable in the axial direction, with the manual operating end 23 of the main valve protruding from the front of the main body case 11. A trigger lever 24 is provided on the front of the main body case 11, and the lower end of the trigger lever 24 is rotatably supported by the main body case 11 by a support pin 25. An engaging piece 26 is provided on the upper end of the trigger lever 24, and the engaging piece 26 engages with a stopper 27 of the main body case 11.

[0013] The manual operation end 23 is in contact with the back of the trigger lever 24. A spring member incorporated in the valve housing 22 applies a spring force to the main valve of the manual valve 21 in the direction toward the trigger lever 24. This applies a pressing force to the trigger lever 24 in the direction that the engaging piece 26 engages with the stopper 27. When the engaging piece 26 is engaged with the stopper 27 of the main case 11, the manual valve 21 is in the closed state, or off state. When the trigger lever 24 is pushed in by the operator, the main valve is driven and the manual valve 21 is switched to the open state, or on state. When the manual valve 21 is switched to the on state, compressed air flows out from the output port of the manual valve 21. As a result, the compressed air flows out into the discharge passage 18 via the communication chamber 20 of the nozzle holder 15 through the internal flow path of the outflow pipe 19 provided between the valve housing 22 and the nozzle holder 15.

[0014] As shown in Figure 1, the unit replacement cover 28 is positioned on the right side of the main case 11 and is provided on the case half 11a so as to be openable and closable. When the unit replacement cover 28, which opens and closes the unit housing chamber 29, is removed from the main case 11 as shown in Figure 3, the unit housing chamber 29 formed in the main case 11 is exposed to the outside. The unit replacement cover 28 is fixed to the main case 11 by screw members or engaging claws (not shown).

[0015] Either the pulse blow unit 31 shown in Figure 4 or the continuous blow unit 41 shown in Figure 5 can be selectively placed in the unit housing chamber 29.

[0016] As shown in Figure 4, the pulse blow unit 31 has a switching valve 32 that converts compressed air supplied from the outside into pulsed, intermittent air. The switching valve 32 is a two-port, two-position directional control valve and has a main valve that is mounted in the valve housing 33 so as to be reciprocating in the axial direction. A small-diameter piston is provided at one end of the main valve and a large-diameter piston is provided at the other end. A small-diameter pilot chamber into which the small-diameter piston is mounted and a large-diameter pilot chamber into which the large-diameter piston is mounted are formed in the valve housing 33.

[0017] An intermittent input end portion 34 through which compressed air is supplied to the switching valve 32 from the outside is provided in the valve housing 33, and the flow path in the intermittent input end portion 34 communicates with the input port of the switching valve 32. The intermittent input end portion 34 has an input joint 35, and an air supply member (not shown) made of a tube or the like is detachably attached to the input joint 35. The air supply member guides compressed air from a compressed air supply source to the intermittent input end portion 34. The intermittent input end portion 34 has a large-diameter flange portion 36, and a small-diameter portion 37 between the input joint 35 and the large-diameter flange portion 36 is detachably attached to an engagement hole 38 formed as an input end attachment portion in the main body case 11.

[0018] An intermittent output end portion 39 is provided in the valve housing 33, and the flow path in the intermittent output end portion 39 communicates with the output port of the switching valve 32. The protruding portion of the intermittent output end portion 39 is detachably attached to a fitting hole 30 formed as a mounting portion in the valve housing 22 of the manual valve 21.

[0019] As will be described later with reference to FIG. 7, the switching valve 32 of the pulse blow unit 31 converts the air supplied from the outside to the intermittent input end portion 34 into intermittent pulse-shaped air and outputs it to the intermittent output end portion 39.

[0020] As shown in FIG. 3, the engagement hole 38 is formed by a semicircular hole formed at the lower end of the case half 11b and a semicircular hole (not shown) formed at the lower end of the unit replacement lid 28. As shown in FIG. 3, when the unit replacement lid 28 is removed from the main body case 11, the pulse blow unit 31 can be taken out from the unit accommodation chamber 29 in the main body case 11. At that time, the intermittent output end portion 39 is removed from the fitting hole 30. If a seal member is provided in the fitting hole 30, the space between the intermittent output end portion 39 and the fitting hole 30 can be sealed.

[0021] As shown in Figure 5, the continuous blow unit 41 has a tube member 42 with a flow path inside, and a continuous input end 43 to which compressed air is supplied from the outside is provided at the lower end of the tube member 42. The continuous input end 43 has an input fitting 44, and an air supply member (not shown) consisting of a tube or the like is detachably attached to the input fitting 44. The continuous input end 43 has a large diameter flange portion 45, and the small diameter portion 46 between the input fitting 44 and the large diameter flange portion 45 is detachably attached to an engagement hole 38 formed in the main body case 11 as an input end mounting portion.

[0022] The upper end of the tube member 42 constitutes a continuous output end 47, which is detachably mounted in a fitting hole 30, which serves as a mounting portion, formed in the valve housing 22 of the manual valve 21. The outer diameter of the small diameter portion 46 of the continuous blow unit 41 is approximately the same as the outer diameter of the small diameter portion 37 of the pulse blow unit 31. Furthermore, the outer diameter of the continuous output end 47 of the continuous blow unit 41 is approximately the same as the outer diameter of the intermittent output end 39 of the pulse blow unit 31. In addition, the length between the large diameter flange portion 45 of the continuous blow unit 41 and the tip of the continuous output end 47 is approximately the same as the length between the large diameter flange portion 36 of the pulse blow unit 31 and the tip of the intermittent output end 39.

[0023] Therefore, either the intermittent input end 34 or the continuous input end 43 can be engaged with the engagement hole 38, and either the intermittent output end 39 or the continuous output end 47 can be fitted into the fitting hole 30 of the manual valve 21. Thus, either the pulse blow unit 31 or the continuous blow unit 41 can be selectively placed in the unit housing chamber 29 of the main body case 11. As a result, the air blow gun 10 can function as either a pulse blow gun or a continuous blow gun.

[0024] Figure 6(A) is an air pressure circuit diagram of the air blow gun 10 when a pulse blow unit 31 is attached to the air blow gun 10, and Figure 6(B) is an air pressure circuit diagram of the air blow gun 10 when a continuous blow unit 41 is attached to the air blow gun 10.

[0025] As shown in Figure 6, the manual valve 21 is a two-port, two-position directional control valve. When the main valve is operated by the trigger lever 24, the input port 51 of the manual valve 21 communicates with the flow path of the outlet pipe 19, turning the manual valve 21 ON, and the compressed air that has passed through the manual valve 21 is discharged from the discharge nozzle 14. On the other hand, when the trigger lever 24 is returned by the spring force of the spring member 48, the manual valve 21 turns OFF, and the communication between the input port of the manual valve 21 and the internal flow path of the outlet pipe 19 is cut off.

[0026] When the pulse blow unit 31 is installed in the unit housing chamber 29, the intermittent output end 39 communicates with the input port 51 of the manual valve 21, and the intermittent input end 34 communicates with an air supply member consisting of a tube or the like connected to the air supply source 52. As shown in Figure 6(A), the pulse blow unit 31 has a switching valve 32 which is a 2-port, 2-position directional control valve, and a small-diameter piston provided at one end of the main valve is incorporated into a small-diameter pilot chamber 53, and a large-diameter piston provided at the other end of the main valve is incorporated into a large-diameter pilot chamber 54.

[0027] The small-diameter pilot chamber 53 communicates with the flow path of the intermittent input end 34 via a pilot flow path 55, and the large-diameter pilot chamber 54 communicates with the flow path of the intermittent output end 39 via a pilot flow path 56. The flow rate of air flowing through the pilot flow path 56 is adjusted by a variable throttle valve 57. A spring member 58 applies a spring force to the main valve in a direction that blocks communication between the input port and the output port. An operating knob 59 for the throttle valve 57 is provided on the pulse blow unit 31, and as shown in Figure 2, a through hole 60 for operating the operating knob 59 from the outside is provided in the grip portion 12. The through hole 60 only needs to be provided in the grip portion 12, and may be provided in the case halves 11a or 11b, or in the unit replacement cover 28. When used as a continuous blow gun, the through hole 60 may be blocked with a seal or plug.

[0028] On the other hand, when the continuous blow unit 41 is installed in the unit housing chamber 29, as shown in Figure 6(B), the continuous output end 47 communicates with the input port 51 of the manual valve 21, and the continuous input end 43 communicates with the air supply member connected to the air supply source 52. As a result, compressed air from the air supply source 52 is supplied directly to the input port 51 of the manual valve 21.

[0029] Figure 7 shows the pneumatic circuit of the air blow gun 10 when the pulse blow unit 31 is installed in the unit housing chamber 29. Figure 7(A) shows the state when no air is supplied from the air supply source 52, in which case the manual valve 21 and the switching valve 32 of the pulse blow unit 31 are in the OFF state. When no air is supplied from the air supply source 52, both are in the OFF state. Figure 7(B) shows the state immediately after air is supplied from the air supply source 52 to the input port of the switching valve 32, and the air supplied to the small-diameter pilot chamber 53 by the pilot flow path 55 causes the switching valve 32 to be in the ON state, with the input port and output port in communication.

[0030] As a result, air is supplied to the large-diameter pilot chamber 54 via the pilot passage 56. Compressed air from the air supply source 52 is supplied to both the small-diameter pilot chamber 53 and the large-diameter pilot chamber 54, but the air supplied to the larger-area large-diameter pilot chamber 54, along with the spring force, switches the switching valve 32 to the off position. The switching time is set by adjusting the variable throttle valve 57. In this way, even if air is supplied to the input port of the switching valve 32, the switching valve 32 remains in the off state unless the manual valve 21 is operated to the ON position.

[0031] As shown in Figure 7(C), when the manual valve 21 is switched to the ON position, air is discharged from the discharge nozzle 14 via the switching valve 32 and the manual valve 21. The compressed air that has passed through the switching valve 32 branches into a flow that passes through the manual valve 21 and a flow that flows into the large-diameter pilot chamber 54. The air flowing into the large-diameter pilot chamber 54 applies a thrust to the main valve in the direction of turning off the switching valve 32, and the air supplied to the small-diameter pilot chamber 53 applies a thrust to the main valve in the direction of turning on the switching valve 32. When the thrust in the direction of turning off the main valve becomes large enough due to the pressure in the large-diameter pilot chamber 54, the switching valve 32 is switched to the OFF position, as shown in Figure 7(D). As a result, the discharge of air from the discharge nozzle 14 is stopped.

[0032] As shown in Figure 7(D), when the switching valve 32 is switched to the off position, the air in the large-diameter pilot chamber 54 is discharged towards the discharge nozzle 14. The discharge speed is adjusted by the throttle valve 57. When the pressure in the large-diameter pilot chamber 54 decreases, the switching valve 32 is switched to the on position, as shown in Figure 7(C). In this way, the switching valve 32 repeatedly switches between the on and off positions, generating a pulse blow that is discharged from the discharge nozzle 14.

[0033] As shown in Figure 4, a tube 61 made of insulating material is incorporated into the discharge nozzle 14 made of conductive material, and a discharge channel 18 is formed inside the discharge nozzle 14 by the tube 61. A discharge electrode 62, which is a discharge needle, is mounted on a nozzle holder 15 made of insulating material. The discharge electrode 62 has a base 63 fixed to the nozzle holder 15, and its tip protrudes into the discharge channel 18 of the discharge nozzle 14. The discharge nozzle 14 made of conductive material constitutes a counter electrode, and when a corona discharge is generated between the discharge nozzle 14 as a counter electrode and the discharge electrode 62, the compressed air flowing in the discharge channel 18 is ionized.

[0034] A power cable 64 is attached to the grip portion 12 of the main body case 11, and a transformer board 65 and a switch board 67 are provided inside the main body case 11. The power cable 64 is connected to the switch board 67, and the switch board 67 is connected to the transformer board 65. An AC high voltage is applied from the power supply unit 66 provided on the transformer board 65 between the counter electrode, which consists of a discharge nozzle 14, and the discharge electrode 62. This causes a corona discharge around the pointed tip of the discharge electrode. When a positive high voltage is applied to the discharge electrode 62, the discharge electrode absorbs electrons from the nearby air, so the nearby air becomes positively charged ions. Conversely, when a negative high voltage is applied to the discharge electrode 62, electrons are emitted from the discharge electrode, so the nearby air becomes negatively charged ions. When ionized air is blown onto charged components such as electronic parts, the charge is neutralized, and the adhesion of foreign matter to the components due to static electricity is prevented.

[0035] An electric switch 67a is provided on the switch board 67. The electric switch 67a is in contact with the back of the trigger lever 24, and when the trigger lever 24 is pushed by the operator, the electric switch 67a turns on, and the compressed air flowing through the discharge channel 18 is ionized.

[0036] An LED lighting fixture 68 is provided at the tip of the main body case 11, allowing the air discharge point to be illuminated by the lighting fixture 68.

[0037] The air blow gun 10 described above can intermittently blow air onto an object when the pulse blow unit 31 is placed in the unit housing chamber 29 of the main body case 11. On the other hand, when the continuous blow unit 41 is placed in the unit housing chamber 29 instead of the pulse blow unit 31, air can be continuously blown onto the object. Thus, the air blow gun 10 has two functions in one unit and can be used as either a pulse blow gun or a continuous blow gun. Furthermore, since the switching between a pulse blow gun and a continuous blow gun can be done simply by changing the unit placed in the unit housing chamber 29, the air blow gun can function as either a pulse blow gun or a continuous blow gun without changing its shape.

[0038] Furthermore, if the target object is a charged component, ionized air can be blown onto the object, preventing the adhesion of foreign matter due to static electricity. On the other hand, if the target object is not charged, non-ionized air can be blown onto the object. To configure the air blow gun 10 to blow non-ionized air, it can be configured as an air blow gun without an insulating tube 61 and discharge electrode 62, etc.

[0039] The present invention is not limited to the embodiments described above, and can be modified in various ways without departing from its spirit. [Industrial applicability]

[0040] The air blow gun of the present invention is used to remove chips, dust, and other debris adhering to the surface of an object, such as a workpiece or painted surface, by blowing compressed air onto the object.

Claims

1. A main body case equipped with an air discharge nozzle, A unit housing chamber is formed in the main body case to selectively house either a pulse blow unit that intermittently outputs air supplied from an external intermittent input terminal to an intermittent output terminal, or a continuous blow unit that continuously outputs air supplied from an external continuous input terminal to a continuous output terminal. A unit replacement lid is provided on the main body case for opening and closing the unit housing chamber, The main body case is provided with a manual valve that can be switched by a trigger lever between an open state, which discharges air discharged from the pulse blow unit or the continuous blow unit to the discharge nozzle, and a closed state, which stops the discharge. An air blow gun that can be used for both continuous blow guns that continuously discharge air towards an object and pulse blow guns that discharge air intermittently.

2. In the air blow gun according to claim 1, The manual valve has a mounting portion to which either the intermittent output end or the continuous output end can be selectively attached, and the main body case has an input end mounting portion to which either the intermittent input end or the continuous input end can be selectively attached, in an air blow gun.

3. In the air blow gun according to claim 1 or 2, The pulse blow unit is an air blow gun provided with a throttle valve and an operating knob for operating the throttle valve, and the main body case is provided with a through hole for operating the operating knob.

4. In the air blow gun according to any one of claims 1 to 3, The pulse blow unit has an intermittent output end that is fitted into the fitting hole of the manual valve, a large-diameter flange and an input joint, and an intermittent input end consisting of a small-diameter portion smaller in diameter than the input joint and the large-diameter flange. The continuous blow unit has a continuous output end that is fitted into the fitting hole of the manual valve, a large-diameter flange and an input joint, and a continuous input end consisting of a small-diameter portion smaller in diameter than the input joint and the large-diameter flange. An air blow gun having an engagement hole in the main body case to which the small-diameter portion of the pulse blow unit or the small-diameter portion of the continuous blow unit is attached.

5. In the air blow gun according to any one of claims 1 to 4, A nozzle holder on which the discharge nozzle is attached is provided in the main body case. A communication chamber is formed in the nozzle holder to guide the air flowing out from the manual valve to the discharge channel provided in the discharge nozzle. An air blow gun is provided in the nozzle holder, wherein a discharge electrode is provided in the nozzle holder that ionizes the air flowing through the discharge channel by generating a corona discharge between the discharge nozzle and the counter electrode, with the discharge nozzle acting as the counter electrode.

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