JP2013043233A - Driving machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving machine capable of achieving an effect of stably and sufficiently reducing air consumption.SOLUTION: The driving machine 1 is provided with a housing 2 on which an accumulator 2a is formed, a trigger 12, a cylinder 3, a piston 4 which divides the cylinder 3 into a cylinder upper chamber 35 and a cylinder lower chamber 36, and a main valve 5 which makes the cylinder 3 communicate with the accumulator 2a while interlocking with the motion of the trigger 12. A return air chamber 34 which communicates to the cylinder 3 and stocks air in the cylinder 3 while interlocking with the motion of the piston 4, and a cylinder control chamber 33 which stocks compressed air in the accumulator 2a while interlocking with the motion of the trigger 12 are formed on the housing 2. The cylinder 3 can move between a bottom dead center which the cylinder upper chamber 35 and the accumulator 2a communicate with each other and a top dead center which the cylinder upper chamber 35 and the accumulator 2a are blocked based on a difference in the pressure of the return air chamber 34 and the cylinder control chamber 33.

Description

  The present invention relates to a driving machine.

  As shown in FIG. 7, the conventional nailing machine 101 includes a housing 102 in which a pressure accumulating chamber 102a in which compressed air is stored, a cylinder 103, and a cylinder 103 accommodated in the cylinder 103, and a cylinder upper chamber and a cylinder lower chamber. And a driver blade 141 for hitting a nail (not shown) fixed to the piston 104, a head valve 105 disposed at the upper part of the cylinder 103, and a trigger 112. A return air chamber 134 is formed in the housing 102, and the piston returns to the top dead center by the compressed air stored in the return air chamber 134. The cylinder 103 is formed with a check valve 103 </ b> A and an air passage 103 a that communicate with the return air chamber 134. A head valve chamber 151 in which the head valve 105 is accommodated is formed above the head valve 105, and the head valve 105 communicates / blocks the pressure accumulating chamber 102 a and the cylinder 103 based on the pressure in the head valve chamber 151. doing.

  In the nailing machine 101, when the operator pulls the trigger 112, the head valve 105 moves to connect the pressure accumulation chamber 102a and the cylinder 103, and the compressed air in the pressure accumulation chamber 102a flows into the cylinder upper chamber. Thereby, the piston 104 is pushed down, and the driver blade 141 drives a nail (not shown) into the material to be driven. As the piston 104 descends, the air in the cylinder lower chamber and the compressed air in the cylinder upper chamber flow into the return air chamber 134 via the check valve 103a and the air passage 103b.

  When the operator returns the trigger 112, the head valve 105 shuts off the pressure accumulation chamber 102a and the cylinder 103, and releases the compressed air in the cylinder upper chamber to the atmosphere from an air passage (not shown).

  As a method for reducing the air consumption of such a nailing machine, for example, Patent Document 1 is known. In the nailing machine described in Patent Document 1, a spring for urging the cylinder downward is provided in the housing. By the trigger operation, the compressed air in the head valve chamber is released, the head valve is raised, the compressed air flows into the cylinder, and the piston is lowered. When the pressure in the return air chamber increases accordingly, the pressure in the return air chamber becomes larger than the biasing force of the spring, the cylinder moves upward, and comes into contact with the head valve. When the trigger is returned, compressed air is supplied to the head valve chamber, and the pressure in the head valve chamber and the urging force of the spring push the cylinder downward, returning the cylinder to the initial position.

JP 2010-64225 A

  In the nailing machine described in Patent Document 1, in order to increase the effect of reducing the air consumption, by setting the urging force of the spring that urges the cylinder weak, the cylinder rises after the head valve rises. Thus, it is effective to shorten the time until the cylinder and the pressure accumulating chamber are shut off, and to suppress the inflow of compressed air into the cylinder. On the other hand, in order to reliably return the cylinder to the initial position, it is effective to increase the biasing force of the spring. Therefore, in the nailing machine described in Patent Document 1, it is necessary to satisfy the conflicting problems of quick upward movement of the cylinder and reliable return to the initial position, and there is still room for improvement in this respect.

  In view of such circumstances, the present invention intends to provide a driving machine capable of obtaining an effect of reducing air consumption stably and sufficiently.

  The present invention relates to a housing in which a first air chamber for storing compressed air is defined, a trigger provided in the housing, a cylinder accommodated in the housing, and a cylinder slidably accommodated in the cylinder. A main valve defining a cylinder upper chamber together with the piston and the cylinder, wherein the piston is divided into an upper chamber and a cylinder lower chamber, and the cylinder and the first air chamber communicate with each other in conjunction with the movement of the trigger. The housing has a second air chamber that communicates with the cylinder and stores air in the cylinder in conjunction with the movement of the piston, and the first air chamber in conjunction with the movement of the trigger. A third air chamber for storing the compressed air of the cylinder, and the cylinder is configured to have the cylinder upper chamber and the first air chamber based on a pressure difference between the second air chamber and the third air chamber. A first position where the It provides a driving machine, wherein a second position in which Linda upper chamber and the first air chamber and is interrupted, the movable.

  According to such a configuration, since the cylinder is moved by the pressure of the compressed air stored in the third air chamber, the cylinder can be moved quickly and stably. Further, since the first air chamber and the cylinder upper chamber are blocked by the movement of the cylinder to the second position, it is possible to prevent excessive compressed air from flowing into the cylinder upper chamber. Thereby, reduction of air consumption can be aimed at stably.

  And a trigger valve portion that communicates or blocks the third air chamber and the first air chamber in conjunction with movement of the trigger, and the trigger valve portion includes the third air chamber and the first air chamber. Preferably, the cylinder moves from the first position to the second position when shutting off.

  According to such a configuration, since the first air chamber and the cylinder upper chamber are shut off after the main valve communicates the cylinder and the first air chamber, excessive compressed air flows into the cylinder upper chamber. Can be prevented. Thereby, reduction of air consumption can be aimed at stably.

  In addition, it further includes a trigger valve portion that communicates or blocks the third air chamber and the first air chamber in conjunction with the movement of the trigger, and one end of the housing opens to the third air chamber, Preferably, an air passage having an end opened to the trigger valve portion is formed, and at least a part of the opening of the air passage can be closed by the cylinder.

  According to such a configuration, since at least a part of the opening is closed by the cylinder, it is possible to prevent a rapid pressure increase in the third air chamber. As a result, the pressure in the third air chamber suddenly rises and the cylinder moves to the first position to prevent the compressed air in the first air chamber from flowing into the cylinder, and the air consumption increases. Can be prevented.

  Further, the housing further defines a fourth air chamber that is controlled to communicate with or shut off from the first air chamber by the trigger valve portion, and the main valve is based on the pressure of the fourth air chamber. It is preferable that communication between the cylinder and the first air chamber is controlled, and the fourth air chamber and the third air chamber communicate with each other.

  According to such a configuration, since the fourth air chamber and the third air chamber communicate with each other, there is no need to provide a valve or the like for controlling the pressure of the third air chamber. Thereby, a driving machine can be manufactured at low cost.

  ADVANTAGE OF THE INVENTION According to this invention, the driving machine which can acquire the effect of air consumption reduction stably and fully can be provided.

The fragmentary sectional view which shows the initial state of the nail driver of the 1st Embodiment of this invention The fragmentary sectional view which shows the state which the piston of the nail driver of the 1st Embodiment of this invention is falling The fragmentary sectional view which shows the state which the piston and bumper of the nail driver of the 1st Embodiment of this invention contact | abut, and the cylinder is located in the top dead center The fragmentary sectional view which shows the initial state of the nail driver of the 2nd Embodiment of this invention The fragmentary sectional view which shows the state which the pressure accumulation chamber and cylinder of the nailing machine of the 2nd Embodiment of this invention connected. The fragmentary sectional view which shows the state which the piston and bumper of the nail driver of the 2nd Embodiment of this invention contact | abut, and the cylinder is located in the top dead center Partial cross-sectional view of a conventional nailer

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. A nail driver 1 which is an example of a driving machine of the present invention is a tool for driving a nail (not shown) which is a stopper, and uses compressed air as its power.

  The nailing machine 1 includes a housing 2, a cylinder 3 accommodated in the housing 2, a piston 4 accommodated in the cylinder 3, a head valve 5 accommodated in the housing 2, and a nose portion 6 extending from the housing 2. And is composed of. The housing 2 includes a handle 2 </ b> A located on one side of the housing 2. In FIG. 1, the direction in which the handle 2 </ b> A extends from the housing 2 is defined as the rear, and the opposite is defined as the front. A direction in which the nose portion 6 extends from the housing 2 is defined as a downward direction, and the opposite direction is defined as an upward direction. Further, a direction orthogonal to the front-rear direction and the up-down direction is defined as a left-right direction (the front side in FIG. 1 is the left direction and the back side is the right direction).

  In order to store compressed air from a compressor (not shown), a pressure accumulating chamber 2 a is formed in the handle 2 </ b> A of the nailer 1 and the housing 2. The pressure accumulating chamber 2a is connected to the compressor via an air hose (not shown). An exhaust port 2 b communicating with the outside is formed in the upper part of the housing 2. The pressure accumulating chamber 2a corresponds to the first air chamber of the present invention.

  At the base of the handle 2A, a trigger 12 that is operated by an operator, a push lever 13 that extends from the lower end of the nose portion 5 to the vicinity of the protrusion trigger 12, and a head valve 31 that will be described later is switched to send and exhaust compressed air. A trigger valve portion 14 that is a valve and a plunger 15 that transmits the operation of the trigger 12 to the trigger valve portion 14 are provided. The push lever 13 is urged from the housing 2 toward the nose portion 5 and can move in the vertical direction along the nose portion 5. A control passage 14 a is formed in the housing 2, and the trigger valve portion 14 is connected to a cylinder biasing chamber 21 described later and a head valve chamber 51 described later by the control passage 14 a.

  The plunger 15 of the trigger valve portion 14 is configured to be pushed up when both the pulling operation of the trigger 12 and the pressing operation of the push lever 13 against the workpiece are performed.

  The cylinder 3 has a substantially cylindrical shape, and is divided into a cylinder upper chamber 35 (FIG. 2) and a cylinder lower chamber 36 by the piston 4. A flange portion 31 that protrudes radially outward from the outer peripheral surface of the cylinder 3 is provided at a substantially central portion in the vertical direction of the cylinder 3. Above the flange portion 31, a partition wall 32 that is slidably in contact with the outer periphery of the cylinder 3 and is fixed to the housing 2 is provided.

  A cylinder control chamber 33 is formed above the flange portion 31 by the outer peripheral surface of the cylinder 3, the flange portion 31, the housing 2, and the partition wall 32. The partition wall 32 is provided with two O-rings 32A for blocking communication between the pressure accumulating chamber 2a and the cylinder control chamber 33. The flange portion 31 blocks communication between the cylinder control chamber 33 and the return air chamber 34. An O-ring 31A is provided. The cylinder control chamber 33 is connected to the trigger valve unit 14 via the control passage 14a. The cylinder control chamber 33 corresponds to the third air chamber of the present invention.

  The cylinder 3 has a top dead center in which the upper end of the cylinder 3 and the head valve 6 are in contact with each other and a lower end of the cylinder 3 is separated from a bumper 43 described later (FIG. 3), a lower end portion of the cylinder 3 and a bumper described later. It is possible to move up and down between the bottom dead center that is in a state of contact with 43 (FIG. 1). The top dead center corresponds to the second position of the present invention, and the bottom dead center corresponds to the first position of the present invention.

  A return air chamber 34 for storing compressed air for returning the piston 4 to the initial state (FIG. 1) is formed on the outer periphery of the lower portion of the cylinder 3. A check valve 3A that can only flow into the return air chamber 34 from the cylinder 3 is provided at the lower portion of the cylinder 3, and an air passage 3a is formed immediately below the check valve 3A. The volume of the return air chamber 34 is configured to be larger than the volume of the cylinder control chamber 33. The return air chamber 34 corresponds to the second air chamber of the present invention.

  The piston 4 is slidable in the vertical direction in the cylinder 3, and a driver blade 41 extending downward is fixed. A piston ring 42 that shuts off the cylinder upper chamber 35 and the cylinder lower chamber 36 is fitted to the outer periphery of the piston 4. Below the cylinder 3 is provided a bumper 43 for absorbing surplus energy of the piston 4 after driving a nail (not shown). The bumper 43 is an elastic body such as urethane or nitrile rubber (NBR).

  The head valve 5 is disposed on the upper side of the cylinder 3, and an air passage (not shown) that can communicate with the exhaust port 2b is formed. A head valve chamber 51 in which the head valve 5 is accommodated is formed in the housing 2. The head valve chamber 51 communicates with the trigger valve portion 14 and the cylinder control chamber 33 via the control passage 14a. A head valve spring 52 that biases the head valve 5 downward is disposed in the head valve chamber 51. In the initial state shown in FIG. 1, the head valve chamber 51 is filled with compressed air, and the head valve 5 is urged downward by the compressed air in the head valve chamber 51 and the head valve spring 52. The force with which the head valve spring 52 urges the head valve 5 downward is smaller than the force with which the compressed air in the pressure accumulating chamber 2a pushes the head valve 5 upward. Therefore, as shown in FIG. 2, when the compressed air in the head valve chamber 51 is released and the atmospheric pressure is reached, the head valve 5 moves upward against the urging force of the head valve spring 52. The head valve chamber 51 corresponds to the fourth air chamber of the present invention.

  The nose portion 6 is located at the lower end of the housing 2 and is formed with a guide path 61 for guiding the driver blade 41 and a nail (not shown). An injection hole through which a nail (not shown) is injected is defined at the lowermost position of the guide path 61. Behind the nose portion 6 is provided a magazine device 62 that houses a bundle of nails in which a plurality of nails (not shown) are bundled and connected. The magazine device 62 is provided with a nail feeder that sequentially feeds nails (not shown) loaded in the magazine 63 into the guide path 51.

  Next, the operation of the nailing machine 1 will be described.

  When an air hose (not shown) is connected, a part of the compressed air accumulated in the pressure accumulating chamber 2a flows into the head valve chamber 51 and the cylinder control chamber 33 via the trigger valve portion 14 and the control passage 14a. The compressed air sent to the head valve chamber 51 pushes down the head valve 5 to further bring the head valve 5 and the cylinder 3 into close contact with each other, thereby preventing the compressed air from flowing into the cylinder 3. The cylinder 3 is urged downward by the compressed air in the head valve 5 and the cylinder control chamber 33, and is located at the bottom dead center.

  When the operator pulls the trigger 12 with the push lever 13 pressed against the workpiece, the plunger 15 is pushed up, and the trigger valve section 14 communicates the control passage 14a with the outside air, thereby controlling the head valve chamber 51 and the cylinder. The chamber 33 is at atmospheric pressure. The head valve 5 moves upward due to the differential pressure between the compressed air stored in the pressure accumulating chamber 2 a and the head valve chamber 51. Thereby, the compressed air stored in the pressure accumulating chamber 2a flows into the cylinder upper chamber 35, pushes down the piston 4, and changes from the state shown in FIG. 1 to the state shown in FIG. At this time, the cylinder control chamber 33 is at atmospheric pressure, but the return air chamber 34 is also at atmospheric pressure, so the cylinder 3 remains at the bottom dead center.

  As the piston 4 descends, the air in the cylinder lower chamber 36 flows into the return air chamber 34 via the check valve 3A and the air passage 3a. When the piston 4 passes through the check valve 3A, the compressed air in the cylinder upper chamber 35 also flows into the return air chamber 34 and presses the flange portion 31 upward. As shown in FIG. 3, when the piston 4 comes into contact with the bumper 43, the cylinder 3 moves to the top dead center. By this movement of the piston 4, a nail (not shown) is driven into the driven material. When the cylinder 3 moves to the top dead center, the upper end of the cylinder 3 and the head valve 5 come into contact with each other, the pressure accumulating chamber 2a and the cylinder upper chamber 35 are shut off, and an excessive flow of compressed air into the cylinder upper chamber 35 is prevented. Is done.

  When the operator returns the trigger 12, the plunger 15 returns and the compressed air is supplied to the cylinder control chamber 33 and the head valve chamber 51 via the control passage 14a. As a result, the head valve 5 moves downward. The cylinder 3 is pushed downward by the compressed air in the head valve 5 and the cylinder control chamber 33, and the head valve 5 and the cylinder 3 move downward together. Thereby, the cylinder 3 moves to the bottom dead center. At the same time, the cylinder upper chamber 35 communicates with the exhaust port 2b through an air passage (not shown), and the cylinder upper chamber 35 becomes atmospheric pressure. Then, the compressed air stored in the return air chamber 34 flows into the cylinder lower chamber 36 through the air passage 3a. As a result, the piston 4 is pushed upward, and the initial state shown in FIG. 1 is obtained.

  According to such a configuration, since the cylinder 3 is moved by the pressure of the compressed air stored in the cylinder control chamber 33, the cylinder 3 can be moved stably. Moreover, since the pressure accumulation chamber 2a and the cylinder upper chamber 35 are shut off by moving the cylinder 3 to the top dead center, it is possible to prevent excessive compressed air from flowing into the cylinder upper chamber 35. Thereby, reduction of air consumption can be aimed at stably.

  According to such a configuration, the cylinder upper chamber 35 and the pressure accumulating chamber 2a are shut off after the head valve 5 communicates the cylinder upper chamber 35 and the pressure accumulating chamber 2a. Inflow can be prevented. Thereby, reduction of air consumption can be aimed at stably.

  According to such a configuration, when the piston 4 drives a nail (not shown) (when the piston 4 and the bumper 43 abut), the cylinder 3 moves to the top dead center, and the cylinder upper chamber 35 and the pressure accumulating chamber. In order to cut off 2a, sufficient energy can be given to the piston 4 until the nail driving (not shown) is completed.

  Next, a nailing machine 201 according to a second embodiment of the present invention will be described with reference to FIGS. In addition, about the same structure as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  A flange portion 231 that protrudes radially outward from the outer peripheral surface of the cylinder 3 is provided at a substantially central portion in the vertical direction of the cylinder 3. In 2nd Embodiment, the length of the up-down direction of the flange part 231 is comprised longer than the flange part 31 of 1st Embodiment. The flange portion 231 is provided with an O-ring 231 </ b> A for blocking the cylinder control chamber 33 and the return air chamber 34.

  The cylinder 3 has a top dead center where the upper end of the cylinder 3 is in contact with the head valve 6 and the upper surface of the flange portion 231 is close to the partition wall 32 (FIG. 6), a lower end portion of the cylinder 3, and a bumper 43 described later. And a bottom dead center where the upper surface of the flange portion 231 is separated from the partition wall 32 (FIG. 4) is movable in the vertical direction.

  In the nailing machine 201, in order to obtain the effect of reducing the air consumption to the maximum, in order to minimize the inflow of compressed air from the pressure accumulating chamber 2a to the cylinder upper chamber 35, the trigger 12 is pulled to It is necessary to reduce the time from when the chamber 35 and the pressure accumulating chamber 2a communicate with each other until the cylinder 3 moves to the top dead center and the cylinder upper chamber 35 and the pressure accumulating chamber 2a are shut off. For this purpose, it is important to quickly release the compressed air from the cylinder control chamber 33 so that the compressed air in the cylinder control chamber 33 does not act as a drag force for pushing the cylinder 3 upward by the pressure in the return air chamber 34. Become. In the second embodiment, the volume of the cylinder control chamber 33 is smaller than that of the first embodiment. Thereby, the compressed air in the cylinder control chamber 33 can be quickly discharged.

  Further, when the volume of the cylinder control chamber 33 is reduced, the pressure rise in the cylinder control chamber 33 when the trigger 12 is returned and the compressed air flows into the cylinder control chamber 33 becomes abrupt. In some cases, the cylinder 3 may move to the bottom dead center earlier than the head valve 5 is lowered. As a result, the cylinder 3 and the head valve 5 are separated from each other and the cylinder upper chamber 35 and the pressure accumulating chamber 2a communicate with each other, so that compressed air flows into the cylinder upper chamber 35 and the air consumption increases. However, in the second embodiment, as shown in FIG. 6, when the cylinder 3 is located at the top dead center, the side surface of the flange portion 231 blocks most of the opening of the control passage 14a. Even if compressed air flows into the cylinder control chamber 33 in this state, a rapid pressure increase in the cylinder control chamber 33 can be suppressed.

  According to such a configuration, since at least a part of the opening is closed by the cylinder 3, a rapid pressure increase in the cylinder control chamber 33 can be prevented. As a result, the pressure in the cylinder control chamber 33 is rapidly increased, the cylinder 3 is moved to the bottom dead center, and the compressed air in the pressure accumulating chamber 2a is prevented from flowing into the cylinder upper chamber 35, and the air consumption is increased. Can be prevented.

  The present invention is not limited to the above-described embodiments, and various improvements and modifications can be made within the scope described in the claims. For example, although a head valve positioned above the cylinder is adopted as an example of the main valve, a structure in which the main valve is disposed on the side surface above the cylinder may be employed.

  In the above-described embodiment, the control passage 14a is communicated with the head valve chamber 51 and the cylinder control chamber 33, so that the cylinder 3 is at the top dead center after the head valve 5 communicates the cylinder 3 and the pressure accumulating chamber 2a. However, the present invention is not limited to this. For example, in order to allow compressed air to flow into the cylinder control chamber 33 at a more appropriate timing, the accumulator chamber 2a and the cylinder control chamber 33 are connected to each other, a valve is provided between them, and the cylinder 3 is moved by opening and closing the valve. good. In this case, a means for discharging the compressed air from the cylinder control chamber 33 is required separately.

1. Nailing machine 2. Housing 3. Cylinder 4. Piston 5. Head valve 6. Nose portion 12. Trigger 14. Trigger valve portion 14a. Control passage 31. Flange portion 32. -Bulkhead 33-Cylinder control chamber 34-Return air chamber 35-Cylinder upper chamber 36-Cylinder lower chamber 41-Driver blade 43-Bumper 51-Head valve chamber

Claims (4)

A housing in which a first air chamber for storing compressed air is defined;
A trigger provided on the housing;
A cylinder housed in the housing;
A piston slidably accommodated in the cylinder and dividing the cylinder into a cylinder upper chamber and a cylinder lower chamber;
A main valve that communicates the cylinder and the first air chamber in conjunction with the movement of the trigger, and that defines the cylinder upper chamber together with the piston and the cylinder;
The housing communicates with the cylinder and stores the air in the cylinder in conjunction with the movement of the piston, and stores the compressed air in the first air chamber in conjunction with the movement of the trigger. A third air chamber is formed,
The cylinder has a first position where the cylinder upper chamber and the first air chamber communicate with each other based on a pressure difference between the second air chamber and the third air chamber, and the cylinder upper chamber and the first air chamber. A driving machine capable of moving between the second position where the air chamber is blocked. A trigger valve portion for communicating / blocking the third air chamber and the first air chamber in conjunction with the movement of the trigger;
The cylinder moves from the first position to the second position when the trigger valve section shuts off the third air chamber and the first air chamber. Machine. A trigger valve portion that communicates or blocks the third air chamber and the first air chamber in conjunction with the movement of the trigger;
The housing has an air passage having one end opened to the third air chamber and the other end opened to the trigger valve portion, and at least a part of the opening of the air passage can be closed by the cylinder. The driving machine according to claim 1, wherein:   The housing further defines a fourth air chamber that is controlled to communicate or block with the first air chamber by the trigger valve portion, and the main valve is connected to the cylinder based on the pressure of the fourth air chamber. 4. The driving machine according to claim 3, wherein communication with the first air chamber is controlled, and the fourth air chamber and the third air chamber communicate with each other.

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