JP2019126846A - Gas combustion type driving tool - Google Patents

Abstract

To provide a gas combustion type driving tool having a simple structure, capable of adjusting output accurately.SOLUTION: A gas combustion type driving tool 10 for driving out a fastener by a combustion pressure generated when igniting gaseous mixture of combustible gas and compressed air supplied into a combustion chamber 12, includes an air spray valve 41 for spraying compressed air into the combustion chamber 12, and a gas spray valve 45 for spraying combustible gas into the combustion chamber 12, in which output related to driving-out of the fastener can be adjusted by adjusting at least either of a filling pressure of the compressed air and a filling pressure of the combustible gas.SELECTED DRAWING: Figure 10

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a gas-fired driving tool for punching out fasteners by the combustion pressure of flammable gas.

  BACKGROUND Conventionally, there has been known a gas-fired type driving tool for pushing out a fastener by the combustion pressure of flammable gas. Also, as a method of improving the output of such a gas combustion type driving tool, there is an idea that the fastener is punched out by the combustion pressure at the time of ignition to the mixture of the flammable gas and the compressed air. That is, although the conventional gas-fired driving tool mixes the atmosphere and the flammable gas, by using the compressed air instead of the atmosphere, a large output is obtained by the energy of the compressed air and the thermal energy of the combustion gas. The method of obtaining was examined.

  In addition, several methods have been proposed for adjusting the output of such a gas-fired tool.

  For example, Patent Document 1 proposes a method of adjusting the output by changing the operation timing of the valve by adjusting the pressure acting on a member (valve) provided between the combustion chamber and the cylinder. ing.

  Further, Patent Document 2 proposes a method of adjusting the output by changing the volume of the combustion chamber.

  In addition, a method of adjusting the output using a known driving depth adjustment mechanism is also conceivable.

Japanese Patent Laid-Open No. 50-15177 JP 63-28574 A

  However, in the configuration described in Patent Document 1 described above, there is a problem that the adjustment of the output is difficult because the operation timing of the valve and the output do not have a linear relationship. In addition, in order to reduce the output, it is necessary to operate the valve at a time when the energy conversion efficiency is low, and there is a problem that the fuel is wasted.

  Further, the configuration described in Patent Document 2 requires a structure for locking the piston in order to change the volume of the combustion chamber, and there is a problem that the structure becomes complicated.

  In addition, even in the method of using the driving depth adjustment mechanism, there is a problem in that the fuel is consumed wastefully and there is a problem that the load on the bumper and the machine is large because the surplus energy is absorbed in the bumper or the like. The

  Then, this invention makes it a subject to provide the gas-fired type | mold driving tool which can adjust an output precisely with a simple structure.

  The present invention has been made to solve the above-described problems, and is a gas combustion type in which a fastener is ejected by a combustion pressure at the time of ignition to a mixture of combustible gas and compressed air supplied into a combustion chamber. A driving tool, comprising: an air injection valve for injecting compressed air into the combustion chamber; and a gas injection valve for injecting flammable gas into the combustion chamber, wherein a filling pressure or flammability of the compressed air in the combustion chamber By adjusting at least one of the gas filling pressures, it is possible to adjust the output related to the launching of the fastener.

  The present invention is as described above, and includes an air injection valve that injects compressed air into the combustion chamber, and a gas injection valve that injects combustible gas into the combustion chamber, and is filled with compressed air filling pressure or combustible gas. By adjusting at least one of the pressure, it is possible to adjust the output related to the launch of the fastener. According to such a configuration, it is possible to change the filling pressure of the mixture by adjusting at least one of the filling pressure of the compressed air and the filling pressure of the flammable gas. Since the filling pressure of the mixture and the output energy are in a proportional relationship, the output can be adjusted with high accuracy. In addition, since the flammable gas can be burned in the most energy efficient state regardless of the output setting, no waste of fuel is consumed. In addition, since a structure for mechanically adjusting the output is not necessary, the structure can be simple.

  It should be noted that the setting of the filling pressure of the mixture may be manually changed by the user of the gas combustion type insertion tool, or the machine may automatically change it based on the input from the sensor or the like. Good.

It is a side view of a gas combustion type driving tool. It is a perspective view of a gas combustion type driving tool. It is a side sectional view of a gas combustion type implantation tool. It is a partially expanded side sectional view of a gas combustion type driving tool. It is the sectional view on the AA line of a gas combustion type implantation tool. It is a side view (a partial BB sectional view) of a gas combustion type implantation tool. It is an enlarged side view (a partial BB sectional view) of a gas combustion type implantation tool. It is a perspective view which shows the internal structure of a gas combustion type | mold driving tool. It is a timing chart which shows operation of a gas combustion type driving tool. It is a table | surface which shows the example of an output setting. It is an enlarged side view (a partial BB sectional view) of a gas combustion type implantation tool concerning a modification. It is a timing chart which shows operation of a gas combustion type implantation tool concerning a modification.

  Embodiments of the present invention will be described with reference to the drawings. In the following description, as shown in FIG. 1, the punching direction of the fastener will be described as "front" and the opposite direction as "rear". Further, the description will be made assuming that the direction of the output portion 11 is “up” and the opposite direction is “down” as viewed in the extending direction of the grip 30 in the direction orthogonal to the fastener launch direction.

  The gas combustion type driving tool 10 according to the present embodiment is configured to eject a fastener by combustion pressure when ignited with respect to a mixture of combustible gas and compressed air, as shown in FIG. 1 and FIG. 2. As shown in FIG. 2, the output unit 11, the grip 30, the gas can storage unit 37, the magazine 38, and the coupler 40 are provided.

  The output unit 11 incorporates a combustion chamber 12 as shown in FIGS. 3 and 4. The combustion chamber 12 is a space for burning a combustible gas, and is for forming a sealable space behind the piston 16 described later (in the direction in which the fastener is ejected). The combustion pressure generated in the combustion chamber 12 acts on the piston 16 and is used to drive out the fastener.

  Further, a nose portion 18 for driving and guiding a fastener toward a material to be driven is attached to the tip of the output portion 11. When a trigger operation unit 31 described later is operated to perform a driving operation, a fastener is formed so as to be driven out to an object to be driven from an injection port 18 a opened at the tip of the nose portion 18.

  The nose portion 18 is configured to be capable of being pushed in with respect to the output portion 11, and in the case where the pushing operation is not performed, the driving operation is not performed even if the trigger operating portion 31 is operated. Specifically, the safety switch (not shown) is turned on when the nose portion 18 is pushed in, and the signal of the trigger switch 32 described later is not effective unless the safety switch is turned on. It is configured. For this reason, since the fastener can not be punched out unless the nose portion 18 is pressed against the workpiece, the safety is secured.

  Inside the housing of the output unit 11 described above, as shown in FIG. 4 etc., the igniter 13, cylinder head 14, cylinder 15, piston 16, driver 17, cylindrical member 20, movable plug 21, compression spring 22 etc. It is housed.

  The igniter 13 is for generating a spark in the combustion chamber 12. For example, the voltage of the battery pack 50 to be described later is boosted to a high voltage, and a spark is generated by discharging the high voltage. Spark plug. The ignition device 13 executes an ignition operation at a predetermined timing based on a signal from a control device 33 described later. When the igniter 13 operates to ignite the mixed gas in the combustion chamber 12, high-pressure combustion gas is generated in the combustion chamber 12, and a piston 16 described later is caused to slide by impact pressure due to the combustion pressure. ing.

  The cylinder head 14 is a member that forms the combustion chamber 12 together with a cylinder 15 described later. The cylinder head 14 is fixed so as to close the rear end of the cylindrical cylinder 15. The cylinder head 14 is provided with an air jet portion 44 and a gas jet portion 48 which will be described later, so that compressed air and combustible gas can be introduced into the combustion chamber 12 from the air jet portion 44 and the gas jet portion 48. It has become.

  The cylinder 15 is a cylindrical member disposed along the longitudinal direction of the output unit 11. The cylinder 15 forms two spaces in front and back. The front space is a space for slidably guiding a piston 16 described later. In addition, the rear space is a space for forming the combustion chamber 12. The two spaces before and after this communicate with each other, and a cylinder member 20 described later is attached between them. Further, the two spaces before and after this can be shielded by the movable stopper 21 accommodated in the cylindrical member 20.

  The piston 16 is a member slidably housed inside the cylinder 15. When a high pressure combustion gas is generated in the combustion chamber 12, the combustion gas acts on the piston 16 so that the piston 16 operates forward.

  The driver 17 is a member for striking a fastener, and is coupled to the front of the piston 16. The driver 17 slides along the injection path of the fastener when the driving operation is performed, and acts to eject the fastener in the injection path from the injection port 18a.

  The cylindrical member 20 is a cylindrical member fixed to the cylinder 15 in the combustion chamber 12. Inside the cylindrical member 20, a pressure chamber 20b for operating a movable stopper 21 described later is formed. Further, a first opening 20a for communicating the combustion chamber 12 with the pressure chamber 20b is provided on the side of the cylindrical member 20. A second opening 20 c is provided on the end face of the cylindrical member 20 on the side of the piston 16 to communicate the combustion chamber 12 with the space behind the piston 16.

  The movable plug 21 is a cylindrical member disposed slidably inside the cylindrical member 20. The movable plug 21 is biased toward the piston 16 by a compression spring 22 and is configured to close the second opening 20c in a natural state. For this reason, in the state before the driving operation, the movable plug 21 shields the combustion chamber 12 and the space behind the piston 16 so that the combustion chamber 12 is sealed.

  Further, a groove is formed on the outer periphery of the movable stopper 21, and the pressure chamber 20 b described above is formed between the groove and the inner peripheral surface of the cylindrical member 20. The pressure chamber 20 b communicates with the combustion chamber 12 in the natural state, and has the same air pressure as that in the combustion chamber 12. Further, a first pressure receiving surface 21a and a second pressure receiving surface 21b are formed at upper and lower edge portions of the groove of the movable plug 21, respectively, so that air pressure is received in the pressure chamber 20b. In the present embodiment, the area of the first pressure receiving surface 21a is formed larger than the area of the second pressure receiving surface 21b, and the movable plug 21 is operated by the difference of the pressure receiving area. That is, when the atmospheric pressure in the pressure chamber 20 b increases, a force that causes the movable plug 21 to slide away from the piston 16 works, and when the force overcomes the urging force of the compression spring 22, the movable plug 21. Is designed to slide backward.

  Therefore, when the air pressure in the pressure chamber 20b (i.e., the combustion chamber 12) exceeds a certain level, the movable plug 21 slides to open the second opening 20c. When the second opening 20 c is opened, the combustion chamber 12 and the space behind the piston 16 communicate with each other, so air (combustion gas) in the combustion chamber 12 flows into the rear of the piston 16. Specifically, when the combustible gas burns in the combustion chamber 12 and the pressure in the combustion chamber 12 rises, the movable plug 21 slides and the combustion gas flows in behind the piston 16 and the piston 16 is moved by the combustion pressure. It is configured to drive.

  The grip 30 is a portion connected to the lower surface of the output portion 11, and is disposed substantially orthogonal to the punching direction of the fastener. The user of the gas-fired driving tool 10 is configured to hold the grip 30 so as to stably hold the tool.

  A trigger operating unit 31 is provided on the grip 30 so as to be pullable. The trigger operating unit 31 is disposed at a position where the forefinger comes in contact with the grip 30. When the trigger operation unit 31 is operated, the trigger switch 32 disposed inside the grip 30 is pressed and turned on. The signal output from the trigger switch 32 turned on is transmitted to the control device 33 disposed inside the grip 30 and processed. Specifically, the control device 33 executes a predetermined driving operation if both the safety switch and the trigger switch 32 described above are on (the driving operation will be described in detail later).

  Further, on the lower end face of the grip 30, a battery mounting portion 34 to which the battery pack 50 can be attached and detached is provided. In order to drive with the electric power supplied from the battery pack 50 which incorporated the secondary battery, the gas combustion type | mold driving tool 10 which concerns on this embodiment is used in the state which mounted | wore the battery mounting part 34 with the battery pack 50. In the present embodiment, the battery pack 50 is configured to be slid from the rear side and mounted on the battery mounting portion 34. Further, the battery pack 50 is configured to be slid backward and removed from the battery mounting portion 34.

  The gas can storage unit 37 is a part for mounting a gas can which is a supply source of the combustible gas supplied to the combustion chamber 12. As shown in FIG. 3, the gas can storage portion 37 according to the present embodiment is formed in a cylindrical shape, and is disposed in front of the grip 30. In addition, the gas can storage portion 37 is disposed such that the central axis is substantially parallel to the grip 30.

  The gas can storage portion 37 according to the present embodiment is provided on the cylindrical portion 37a for slidably holding the gas can, the connection portion 37b provided at the deepest portion of the cylindrical portion 37a, and on the front side of the cylindrical portion 37a. A lid portion 37d.

  The connection portion 37 b is a portion for connecting the nozzle of the gas can. The connection portion 37 b is connected to a first gas pipeline 46 described later. By connecting the nozzle of the gas can to the connection portion 37 b, the flammable gas in the connected gas can can be introduced to the combustion chamber 12.

  The lid portion 37 d is attached to the gas can storage portion 37 so as to be openable and closable. Specifically, the lid portion 37 d is rotatably supported by the gas can storage portion 37 via a hinge 37 c so that the inside of the gas can storage portion 37 can be opened or sealed by rotation. It has become. By opening the lid portion 37d, the gas can accommodated in the gas can accommodating portion 37 can be taken out, or the gas can can be inserted into the gas can accommodating portion 37.

  The magazine 38 is for loading a plurality of punchable fasteners, and is arranged below the nose portion 18. The fasteners loaded in the magazine 38 are sequentially supplied to the nose portion 18, and the leading fastener supplied to the nose portion 18 is struck and driven out by the driver 17. The magazine 38 according to the present embodiment can accommodate connecting fasteners aligned in a straight line.

  The coupler 40 is for connecting a plug of a hose or the like connected to an air supply source such as an air compressor, and for taking in compressed air from the outside. The coupler 40 is disposed on the lower end portion side of the grip 30, and more specifically, is disposed below the position of the grip 30 that can be gripped by the user. Further, the coupler 40 is opened downward. The gas combustion type driving tool 10 according to this embodiment sends compressed air supplied from the outside through the coupler 40 to the combustion chamber 12 and uses it for driving a fastener.

  As shown in FIG. 2, the coupler 40 is provided at a position offset to the side as viewed from the grip 30 (left side as viewed from the user holding the grip 30). Specifically, it is provided on the side of the gas can storage portion 37. Further, the coupler 40 is disposed to be shifted forward of the battery mounting portion 34. Thus, the coupler 40 is disposed offset to the battery mounting portion 34 or the gas can storage portion 37, and is disposed close to the battery mounting portion 34 and the gas can storage portion 37. It is disposed so as not to interfere with the gas can storage portion 37. For this reason, parts requiring attachment / detachment operations such as the battery mounting portion 34, the gas can storage portion 37, and the coupler 40 are arranged together on the lower end side of the grip 30, and the operability is good. In addition, since these are arranged in a compact form, the machine does not become large, making it easy to handle.

  Further, as shown in FIG. 1, the coupler 40 is provided so as not to protrude below the battery pack 50 mounted on the battery mounting portion 34. For this reason, since the coupler 40 does not protrude from the outline of the tool, the handling of the tool when the hose is connected is good. Further, the coupler 40 is arranged inside the outline of the tool so that the coupler 40 is less likely to come into contact with the ground when the tool is placed on the ground or the like, and dust or the like is less likely to adhere to the coupler 40. It has become.

  Next, the introduction path of the compressed air and the flammable gas into the combustion chamber 12 will be described.

  The externally supplied compressed air is introduced into the tool via the coupler 40 as described above. The gas combustion type implantation tool 10 according to the present embodiment is provided with a pipeline for connecting the coupler 40 and the combustion chamber 12. Specifically, a first air pipe 42 that constitutes an introduction path from the coupler 40 to an air injection valve 41 (described later), and a second air pipe that constitutes an introduction path from the air injection valve 41 to the combustion chamber 12. And 43.

  The first air conduit 42 is a pipe whose upstream end is connected to the coupler 40 and whose downstream end is connected to the air injection valve 41. As shown in FIGS. 1 and 8, the first air pipeline 42 is disposed on the upstream side along the side surface of the gas can containing portion 37. Further, the first air pipeline 42 is disposed along the side surface of the output section 11 at the downstream side. Since the gas can storage portion 37 and the output portion 11 are connected in a substantially L shape, the first air pipeline 42 is bent in an L shape at the connection point between the gas can storage portion 37 and the output portion 11 . The first air pipeline 42 according to the present embodiment is formed of a tube that can be elastically bent.

  Further, the first air pipeline 42 is attached with a part thereof exposed outside the tool housing. More specifically, the first air conduit 42 penetrates a tunnel-like conduit holding portion 37 e provided on the side surface of the gas can storage portion 37 and on the conduit cover portion 25 provided on the side surface of the output portion 11. The other parts are exposed to the outside. According to such a configuration, since the first air pipe 42 is inserted and assembled from the outside of the housing, the assemblability is good.

  The air injection valve 41 is a solenoid valve that controls the amount of compressed air supplied to the combustion chamber 12. The air injection valve 41 measures compressed air supplied through the first air line 42 and injects a fixed amount of compressed air into the combustion chamber 12. As shown in FIG. 6, the air injection valve 41 according to the present embodiment is disposed adjacent to the combustion chamber 12. For this reason, the distance of the 2nd air pipe line 43 mentioned later can be set short, and the response of a machine can be improved.

  The second air pipeline 43 is a pipe whose upstream end is connected to the air injection valve 41 and whose downstream end is connected to the combustion chamber 12. The second air pipe 43 is for introducing the compressed air injected by the air injection valve 41 into the combustion chamber 12. The second air conduit 43 is disposed to wrap around the rear of the cylinder head 14 as shown in FIGS. 6 and 8. As shown in FIGS. 5 and 7, the cylinder head 14 is provided with an air ejection portion 44 for connecting the second air pipe 43, and the compressed air that has passed through the second air pipe 43 is air. It flows into the inside of the combustion chamber 12 through the jet part 44.

  In addition, the 2nd air pipeline 43 which concerns on this embodiment is formed by the tube which can be elastically bent. As a result, even if vibration or impact occurs at the time of driving operation, it is difficult to damage or detach.

  Further, the combustible gas in the gas can is introduced through the connection part 37b of the gas can storage part 37 as described above. The gas combustion type implantation tool 10 according to the present embodiment is provided with a pipeline for connecting the connection portion 37 b and the combustion chamber 12. Specifically, a first gas pipe 46 constituting an introduction path from the connection portion 37b to a gas injection valve 45 (described later), and a second gas pipe constituting an introduction path from the gas injection valve 45 to the combustion chamber 12 And a road 47.

The first gas pipe 46 is a pipe having an upstream end connected to the connecting portion 37 b and a downstream end connected to the gas injection valve 45. As shown in FIG. 3, the first gas pipe 46 is disposed along the output unit 11.
The gas injection valve 45 is an electromagnetic valve that controls the amount of combustible gas supplied to the combustion chamber 12. The gas injection valve 45 measures the combustible gas supplied through the first gas line 46 and injects a certain amount of combustible gas into the combustion chamber 12. As shown in FIG. 4, the gas injection valve 45 according to the present embodiment is disposed adjacent to the combustion chamber 12. For this reason, the distance of the 2nd gas pipe line 47 mentioned later can be set short, and the response of a machine can be improved.

  The second gas conduit 47 is a pipe whose upstream end is connected to the gas injection valve 45 and whose downstream end is connected to the combustion chamber 12. The second gas pipe 47 is for introducing the combustible gas injected by the gas injection valve 45 into the combustion chamber 12. The second gas line 47 is disposed so as to wrap around the rear of the cylinder head 14 as shown in FIGS. 4 and 8. As shown in FIG. 5, the cylinder head 14 is provided with a gas ejection portion 48 for connecting the second gas conduit 47, and the combustible gas having passed through the second gas conduit 47 is a gas ejection portion It flows into the interior of the combustion chamber 12 via 48. In addition, the 2nd gas pipeline 47 which concerns on this embodiment is formed by the tube which can be bent elastically. As a result, even if vibration or impact occurs at the time of driving operation, it is difficult to damage or detach.

  Next, the driving operation of the gas combustion driving tool 10 according to the present embodiment will be described with reference to FIG.

  When the trigger operation unit 31 is operated and the driving operation is started, first, the control device 33 operates to open the gas injection valve 45 at the timing shown in A of FIG. Then, the gas injection valve 45 is opened until a predetermined time passes, and when the predetermined time passes, the gas injection valve 45 is closed at the timing shown in B. Thereby, a predetermined amount of combustible gas is supplied into the combustion chamber 12.

  Next, the controller 33 opens the air injection valve 41 at the timing shown in FIG. Then, the air injection valve 41 is opened until a predetermined time passes, and when the predetermined time passes, the air injection valve 41 is closed at the timing shown in D. As a result, a predetermined amount of compressed air is supplied into the combustion chamber 12.

  When the combustible gas and the compressed air are introduced into the combustion chamber 12 to generate an air-fuel mixture, the controller 33 operates the igniter 13 at the timing shown in FIG. 9E to ignite the air-fuel mixture. As a result, the pressure in the combustion chamber 12 rapidly increases. When the pressure in the combustion chamber 12 is increased, the movable stopper 21 is operated and the combustion gas flows into the rear of the piston 16. As a result, the combustion pressure acts on the piston 16 to slide, and the fastener is punched out by the driver 17 sliding integrally with the piston 16.

  Here, by adjusting the filling pressure of the compressed air in the combustion chamber 12 and the filling pressure of the flammable gas, the gas combustion driving tool 10 according to the present embodiment can adjust the output relating to the launch of the fastener. It is configured. Specifically, the output is adjusted by adjusting the opening time of the air injection valve 41 and the gas injection valve 45. Adjustment of the opening times of the air injection valve 41 and the gas injection valve 45 is realized by the control device 33 changing the energization time to the air injection valve 41 and the gas injection valve 45.

  In the present embodiment, the user of the gas combustion driving tool 10 can set the output in multiple stages. For example, as shown in FIG. 10, the output can be selected from three levels of “strong”, “medium”, and “weak”. The gas-fired implantation tool 10 according to the present embodiment includes an operation unit 35 (see FIG. 3) such as a button or a knob for changing the output, and the operation unit is operated to input user input. Get the external parameter based. Then, the output is adjusted with reference to this external parameter.

In this embodiment, “medium” is a normal output, and the opening time of the air injection valve 41 and the gas injection valve 45 when set to “medium” is “1” which is a reference value. . In addition, when it is set to “strong”, the opening times of the air injection valve 41 and the gas injection valve 45 become “1.2” which is 1.2 times the value of “medium”. In addition, when “weak” is set, the opening times of the air injection valve 41 and the gas injection valve 45 become “0.7” which is 0.7 times the value of “medium”. Thus, in the present embodiment, both the opening time of the air injection valve 41 and the opening time of the gas injection valve 45 are configured to be longer in proportion to the output. In the present embodiment, the ratio between the opening time of the air injection valve 41 and the opening time of the gas injection valve 45 is configured to be constant regardless of the output, but is not limited to this and is set. The ratio may be arbitrarily set according to the output.
The opening time of the air injection valve 41 and the opening time of the gas injection valve 45 thus determined are used for control by the control device 33 in the driving operation shown in FIG. That is, the control device 33 waits until the determined opening time of the gas injection valve 45 elapses after opening the gas ejection portion 48 at the timing shown in FIG. The gas ejection part 48 is closed at the timing shown. Further, the control device 33 waits until the determined opening time of the air injection valve 41 elapses after opening the air injection valve 41 at the timing shown in FIG. 9C. The air injection valve 41 is closed at the timing shown.

  In the present embodiment, the output can be selected from multiple stages. However, the present invention is not limited to this, and the output may be selected steplessly.

  Further, in the above-described embodiment, the output can be selected from three stages of "strong", "medium" and "weak", but the invention is not limited thereto, and the "operation mode" which can obtain an output suitable for the application May be selectable. Further, the user may select the nail and the driving member to be used, and output adjustment based on a preset parameter may be performed according to the selected condition.

  Further, the opening time of the air injection valve 41 and the opening time of the gas injection valve 45 according to the output set by the user may be further adjusted with reference to the use environment of the machine. For example, environmental temperature, machine temperature, supply pressure of compressed air to the air injection valve 41, supply pressure of gas fuel to the gas injection valve 45, pressure in the pipeline, pressure in the combustion chamber 12, flow rate in the pipeline, One or more factors such as the power supply voltage may be obtained, and the opening time may be adjusted accordingly. In this way, stable driving force can be always obtained even in different use environments.

  In this embodiment, an example in which the user changes the output has been described. However, the present invention is not limited to this, and the machine may automatically change the output based on an input from a sensor.

  For example, as shown in FIG. 11, a pressure sensor 49 may be provided downstream of the air injection valve 41 and the gas injection valve 45 as a sensor. Then, when the pressure in the combustion chamber 12 (inside the pipeline) detected by the pressure sensor 49 reaches a predetermined pressure set in advance, the control device 33 operates to close the air injection valve 41 or the gas injection valve 45. You may

  Although the pressure sensor 49 is provided on the downstream side of the air injection valve 41 and the gas injection valve 45 in the above example, the pressure sensor 49 is not limited to this, and the pressure sensor 49 is disposed on the upstream side of the air injection valve 41 and the gas injection valve 45 You may

  Further, although the example in which the pressure sensor 49 is provided as the sensor has been described in the above example, in addition to or in place of the pressure sensor 49, the inside of the flow path in which the air injection valve 41 is disposed or gas injection A flow sensor may be provided in the flow path in which the valve 45 is disposed. Then, when the flow rate detected by the flow sensor reaches a predetermined flow rate set in advance, the control device 33 may close the air injection valve 41 or the gas injection valve 45.

  In addition to the pressure sensor 49 and the flow rate sensor, or in place of the pressure sensor 49 and the flow rate sensor, a temperature sensor may be provided to detect an environmental temperature. Then, using the environmental temperature detected by the temperature sensor as an input parameter, the control device 33 may control the air injection valve 41 or the gas injection valve 45 to adjust the output.

  Further, in addition to (or instead of) the control as described above, the output may be adjusted by adjusting the supply pressure to the air injection valve 41 or the gas injection valve 45. For example, if the supply pressure to the air injection valve 41 or the gas injection valve 45 is unstable, the output may not be stable, so the supply pressure of these may be made constant.

  Specifically, the supply pressure to the gas injection valve 45 may be adjusted by changing the temperature of the gas can that is the supply source of the flammable gas. Since the vapor pressure of the gas fuel increases with temperature, when the temperature of the gas can changes, the supply pressure to the gas injection valve 45 also changes. When it is not desired to cause such a change, the supply pressure to the gas injection valve 45 can be stabilized by keeping the temperature of the gas can storage portion 37 constant. Further, the supply pressure to the gas injection valve 45 can be changed by intentionally changing the temperature of the gas can storage unit 37.

  Further, the pressure supplied to the air injection valve 41 may be adjusted by using a pressure reducing valve. Since the supply pressure to the air injection valve 41 depends on the internal pressure of the tank of the air compressor connected to the outside, if the internal pressure of the tank is lowered due to the remaining amount of compressed air, the supply pressure to the air injection valve 41 is also descend. When such a change is not desired, if the compressed air supplied from the air compressor is supplied to the air injection valve 41 via the pressure reducing valve, the supply pressure can be made constant by the pressure reducing valve. Moreover, if the pressure reducing valve is made detachable, the supply pressure to the air injection valve 41 can also be changed. In addition, when making a pressure-reduction valve detachable, you may provide the attachment or detachment mechanism of a pressure-reduction valve in the coupler 40, for example.

  In the embodiment described above, the output is adjusted by adjusting the opening time of the air injection valve 41 and the gas injection valve 45, but additionally (or instead) to the combustion chamber 12 The output may be adjusted by adjusting the flow passage area of the flow passage for supplying the compressed air or the flammable gas. For example, the flow rate of the compressed air or the flammable gas may be adjusted by adjusting the opening amount of the air injection valve 41 or the gas injection valve 45. Specifically, the air injection valve 41 or the gas injection valve 45 capable of adjusting the opening amount is used, and the flow rate is adjusted by adjusting the opening amount of the air injection valve 41 or the gas injection valve 45, thereby the combustion chamber. The amount of compressed air or flammable gas supplied to 12 may be adjusted. In addition, the flow rate of compressed air or combustible gas may be adjusted by switching the flow path itself. Specifically, a plurality of pipelines with different areas are provided, and the flow rate is adjusted stepwise by switching which pipeline is communicated with the combustion chamber 12, whereby the compressed air or the combustible supplied to the combustion chamber 12 is adjusted. The amount of sexing gas may be adjusted.

  In addition to the control described above, the output may be adjusted by changing the ignition timing. For example, as shown in FIG. 12, the ignition timing (E ') may be advanced to cause ignition before the filling pressure in the combustion chamber 12 increases, thereby changing the output.

  As described above, according to the present embodiment, the air injection valve 41 that injects compressed air into the combustion chamber 12 and the gas injection valve 45 that injects combustible gas into the combustion chamber 12 are provided. According to such a configuration, even if the volume of the combustion chamber 12 is not extremely increased, a large output can be obtained by the energy of the compressed air and the thermal energy of the combustion gas. Specifically, an output comparable to that of a pyrotechnic driving tool can be obtained with a machine size in a practical range as a hand-held tool. Moreover, unlike the explosive driving tool, it can be used without a special license and is easy to maintain.

  Then, by adjusting at least one of the filling pressure of the compressed air and the filling pressure of the flammable gas, the output relating to the launch of the fastener can be adjusted. According to such a configuration, since the filling pressure of the air-fuel mixture and the output energy are in a proportional relationship, the output can be adjusted with high accuracy. In addition, since the flammable gas can be burned in the most energy efficient state regardless of the output setting, no waste of fuel is consumed. In addition, since a structure for mechanically adjusting the output is not necessary, the structure can be simple.

DESCRIPTION OF SYMBOLS 10 Gas combustion type driving tool 11 Output part 12 Combustion chamber 13 Ignition device 14 Cylinder head 15 Cylinder 16 Piston 17 Driver 18 Nose part 18a Injection port 20 Cylindrical member 20a 1st opening part 20b Pressure chamber 20c 2nd opening part 21 Movable stopper 21a 1st pressure receiving surface 21b 2nd pressure receiving surface 22 Compression spring 25 Pipe line cover part 30 Grip 31 Trigger operation part 32 Trigger switch 33 Control device 34 Battery mounting part 35 Operation part 37 Gas can storage part 37a Tube part 37b Connection part 37c Hinge 37d Lid part 37e Pipe line holding part 38 Magazine 40 Coupler 41 Air injection valve 42 First air pipe line 43 Second air pipe line 44 Air injection part 45 Gas injection valve 46 First gas pipe line 47 Second gas pipe line 48 Gas discharge 49 Pressure sensor 50 Battery pack

Claims (13)

A gas combustion type driving tool for driving a fastener by combustion pressure when ignited with respect to a mixture of combustible gas and compressed air supplied into a combustion chamber,
An air injection valve for injecting compressed air into the combustion chamber;
A gas injection valve for injecting combustible gas into the combustion chamber;
With
A gas combustion type driving tool characterized in that an output related to driving of a fastener can be adjusted by adjusting at least one of a filling pressure of compressed air and a filling pressure of a combustible gas in the combustion chamber.   The gas-fired insert tool according to claim 1, wherein the output is adjusted by adjusting the opening time of at least one of the air injection valve and the gas injection valve.   The opening time of the air injection valve or the gas injection valve is adjusted by changing an energization time or supply power amount to at least one of the air injection valve or the gas injection valve. 2. A gas-fired driving tool according to 2.   The gas combustion type driving according to any one of claims 1 to 3, wherein the output is adjusted by adjusting a supply pressure to at least one of the air injection valve and the gas injection valve. tool.   The gas combustion type driving tool according to claim 4, wherein a supply pressure to the gas injection valve is adjusted by changing a temperature of a gas can as a supply source of the combustible gas.   The gas combustion type driving tool according to claim 4 or 5, characterized in that the pressure supplied to the air injection valve is adjusted by using a pressure reducing valve.   The gas combustion type driving tool according to any one of claims 1 to 6, wherein the output is adjusted by adjusting an opening amount of at least one of the air injection valve or the gas injection valve. .   A gas-fired tool insert according to any of the preceding claims, characterized in that the output is adjusted with reference to external parameters based on sensor input or user input.   The gas combustion type driving tool according to claim 8, further comprising a pressure sensor on the upstream side or the downstream side of at least one of the air injection valve and the gas injection valve as the sensor.   The gas combustion type driving tool according to claim 8, further comprising a flow rate sensor in a flow path in which at least one of the air injection valve and the gas injection valve is disposed as the sensor.   The gas combustion type driving tool according to claim 8, further comprising a temperature sensor that detects an environmental temperature as the sensor.   The gas combustion type driving tool according to any one of claims 1 to 11, wherein the output is adjusted by changing the timing of the ignition.   The gas combustion type driving tool according to any one of claims 1 to 12, further comprising an operation unit for adjusting an output related to punching of a fastener.

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