JP5348604B2 - Driving machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driver machine capable of providing improved durability of a driver blade without increasing reaction upon driving in a locking device, and preventing breakage due to stress concentration on a pin fitting hole part of the driver blade. <P>SOLUTION: A boss 4a is formed at a lower part of a piston 4 that can slide inside a cylinder of the driver machine in a vertical direction, a fitting groove to which an attachment part 6a of the driver blade 6 is fitted is formed at the boss 4a, and a pin 5 is pressed in a circular hole provided at the boss 4a. A hole to which the pin 5 is fitted is formed in the attachment part 6a of the driver blade 6 toward a driving-in direction from an outer circumference of the pin 5 to form in a longitudinal hole 7, and curve line parts that form an arc 8 are formed at both ends in a width direction. An upper edge 9a of the driver blade 6 is inserted to be abutted on a bottom part 10a of the fitting groove, and the driver blade 6 is fixed at the piston 4 so that an upper part of the pin 5 may be abutted on the driver blade 6, but a lower part of the pin 5 may not be abutted on the driver blade 6. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a driving machine for driving a driver blade by a piston driven by compressed air and driving a stopper such as a nail, and more particularly, a driving blade connected to the piston and improved in its mounting method. Related to embedded machines.

  Generally, in a driving machine, a driver blade is used to drive a stopper such as a staple or a nail into a material to be driven such as wood, and the driver blade is fixed to a lower portion of a piston that receives pressure of compressed air. As shown in FIGS. 8 and 9, the piston structure is such that a fitting groove 10 is formed from below to above in a boss 4a formed integrally with the piston 4 below (stopping direction of the stopper). The mounting portion 6a of the driver blade 6 having substantially the same shape as that of the screw 10 is fitted into the fitting groove 10, and the pin 5 is press-fitted into the circular hole 12 provided in the boss 4a and the hole 11 provided in the driver blade 6. Then, the driver blade 6 is attached to the piston 4. A load (a reaction force received from the stopper) generated when the stopper is driven is configured to be received by the bottom surface 10 a of the fitting groove 10 via the upper end portion 9 a of the driver blade 6. Such a driving machine is disclosed, for example, in Patent Document 1 below.

JP-A-9-109056

  However, in the above configuration, when a driving operation is performed without noticing that relatively soft wood or fasteners are lost, an excessive load is generated in the driving direction, and the load is applied to the pin 5 and the driver blade 6. It will be received at the hole 12. Therefore, stress concentrates on a specific part around the hole 12 of the driver blade 6 and the driver blade 6 may be damaged.

  This situation will be further described. FIG. 10 is a conceptual diagram for explaining the force applied to the piston 4, the driver blade 6, the stopper 22 such as a nail, and the pin 5 during the driving operation of the driving machine. These are written schematically for the sake of explanation, and their shapes and dimensions do not match those of the actual apparatus.

  In FIG. 10 (1), when a trigger (not shown) of the driving machine is pulled, a strong force 31 that momentarily pushes down the piston 4 by the compressed air acts, and the force is transmitted to the driver blade 6, and the driver blade The force 32 that presses the stopper 22 is applied at the lower end portion 9 b of 6. At this time, the driver blade 6 directly receives a strong force from the piston 4 because the upper end portion 9a is mainly in contact with the bottom surface 10a of the fitting groove of the piston. Next, in FIG. 10B, when the piston 4 moves to near the lower end of the stroke, the piston 4 collides with the damper 15, receives the repulsive force 33 of the damper, and the downward movement of the piston 4 stops (this The stop position is called “bottom dead center”). At this time, the movement of the driver blade 6 is similarly stopped. However, since the reaction force 34 of the stopper 22 driven into the driven material 23 is received from below, the driver blade 6 is compressed from above and below. Receive power.

  The above is the operation during normal driving. However, if the driving is performed without noticing that the stopper has been lost (this is called “empty driving”) or the driving is performed on relatively soft wood, the piston 4 Is moved to near the lower end of the stroke, there is no or little reaction force from the stopper as shown in FIG. 10 (3), so the driver blade 6 has a strong force in the direction of the arrow 35 at its center of gravity. Acts to leave the piston 4 and jump out downward. This force is received by the reaction force 35 of the pin 5 that penetrates the boss of the piston 4 as shown in the partially enlarged view of FIG. However, at this time, a strong surplus load (stress) is applied to the portion 25 shown in FIG. 10 (5), and if such a blanking is repeated or the number of times is large, there is a possibility that a crack 26 may be generated in the worst case. . In FIG. 10 (5), the shape of the crack 26 is drawn in a waveform, but this is only drawn schematically for the sake of explanation and does not match the actual shape. Further, in FIG. 10 (4), in order to make the positional relationship between the pin 5 and the hole 12 of the driver blade 6 easy to understand, there is a gap between them, but in actuality, it is closely attached by press fitting or the like. There are no gaps.

  In order to improve the strength of the driver blade 6, the thickness of the mounting portion 6a of the driver blade 6 fitted to the piston 4 can be increased or the width can be increased. As a result, the driver blade 6 becomes heavy, and there is a problem that the recoil when the stopper is driven becomes large.

  Further, it is conceivable that the driver blade 6 is firmly fixed to the piston 4 by bonding or welding. However, in this case, the productivity is deteriorated and the cost is increased. Furthermore, it is conceivable to change the driver blade 6 to a strong material, but this leads to an increase in cost.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a driving machine capable of improving the durability of the driver blade without increasing the reaction when driving the stopper. is there.

  Another object of the present invention is to provide a driving machine that is inexpensive, has good assemblability, and can prevent problems caused by local generation of stress in a driver blade.

  Of the inventions disclosed in the present application, typical features will be described as follows.

  According to one aspect of the present invention, a pressure accumulating chamber that stores compressed air, a cylinder that can communicate with the pressure accumulating chamber, a piston that reciprocates up and down in the cylinder, and a groove that is formed upward from the lower portion of the piston The driver blade fixed to the piston is driven by driving the piston by instantaneously supplying the compressed air stored in the pressure accumulating chamber into the cylinder. In a driving machine for driving a stopper into a material to be driven by pushing the stopper, the upper end of the driver blade is inserted into contact with the bottom of the groove, and a hole through which the pin of the driver blade passes is inserted into the pin The shape was larger than the diameter.

  The hole of the driver blade is long in the moving direction of the piston and short in the direction perpendicular to the moving direction. In that case, the length in the longitudinal direction of the hole is preferably 10% or more, and particularly preferably 50% or more larger than the length in the lateral direction.

  Further, the hole of the driver blade may be an ellipse having a long radius in the moving direction of the piston and a short radius in the moving direction and the vertical direction, or an elliptical shape in which two semicircles are connected by a straight line. In this case, the driver blade is attached to the piston so that the lower part of the pin does not contact the driver blade.

  A boss protruding downward is formed in the lower part of the piston, and a groove for inserting a driver blade is formed in the boss upward from the lower end of the boss. Further, the boss is formed with a hole for inserting a pin in the lateral direction so as to cross the groove.

  The shape of the mounting portion of the driver blade fixed to the piston is a substantially rectangular flat plate shape, has an arcuate outline inward on one side or both sides of the side, and the width in the vicinity of the central portion in the vertical direction of the mounting portion. However, it is comprised so that it may become narrower than the width | variety in the up-down direction edge part of an attaching part. Alternatively, an arc-shaped notch having a vertex in the hole direction is formed on the side of the mounting portion.

According to the first aspect of the present invention, the hole through which the pin of the driver blade is penetrated has a shape larger than the pin, is long in the moving direction of the piston, is short in the direction perpendicular to the moving direction, and the upper portion of the pin is the driver. Since the lower part of the pin is fixed so that it touches the blade and does not touch the driver blade, the excess load in the driving direction generated during the blanking operation is dispersed without being concentrated in one place of the hole of the driver blade. The stress generated at the edge can be effectively dispersed, and the durability of the driver blade can be improved. Further, since the hole of the driver blade is an ellipse having a long radius in the moving direction of the piston, the durability of the driver blade having a simple shape can be improved.

According to the invention of claim 2 , since the hole of the driver blade is an ellipse having a long radius in the moving direction of the piston, the durability of the driver blade having a simple shape can be improved.

According to invention of Claim 3 , since the hole of the driver blade was made into the ellipse shape which connected two semicircles with the straight line, it is easy to drill with a drill etc. and is excellent in workability at the time of manufacture.

According to the invention of claim 4 , since the length in the moving direction of the piston is 10% or more larger than the diameter of the pin and a gap is surely formed in the lower part of the pin, a strong excessive load is effectively applied to a part of the driver blade. Can be dispersed.

According to the invention of claim 5 , since the hole for inserting the pin in the lateral direction is formed in the boss at the lower part of the piston so as to cross the groove, the workability when replacing the driver blade is improved. Can do.

According to the sixth aspect of the present invention, since the arcuate contour is formed on one side or both sides of the side of the mounting portion of the substantially square driver blade, the stress generated in the hole portion of the driver blade is further dispersed. be able to.

According to the invention of claim 7 , since the arc-shaped notch having the apex in the hole direction is formed on one side or both sides of the side of the mounting portion of the substantially square driver blade, the stress generated in the hole portion of the driver blade Can be further dispersed.

According to the invention of claim 8 , the center of the hole of the driver blade is offset so as to be positioned below the circumferential center of the cylindrical or cylindrical pin, and the driver blade is fixed to the boss of the piston. Therefore, the stress generated in the hole portion of the driver blade can be dispersed, and the durability of the driver blade can be improved. Further, since the driver blade can be reduced in weight, the reaction at the time of driving can be reduced.

  The above and other objects and novel features of the present invention will become apparent from the following description and drawings.

  One embodiment of the present invention is shown in FIGS. FIG. 1 is a partial cross-sectional view of a driving machine showing an embodiment of the present invention for driving a stopper such as a finishing nail or a staple. 2 is a perspective view showing the appearance of the piston, FIG. 3 is a cross-sectional view showing the mounting structure of the piston and the driver blade of the driving machine, and FIG. 4 is a cross-sectional view taken along line AA in FIG. It is another sectional view.

  As shown in FIG. 1, in the driving machine 1, compressed air from a compressor (not shown) is accumulated in a pressure accumulating chamber 2 in the driving machine 1 via an air hose (not shown). The driving machine 1 is provided with a cylinder 3 communicating with the pressure accumulating chamber 2, and a piston 4 that reciprocates in the vertical direction is installed in the cylinder 3. Below this piston 4 (in the nail driving direction), a boss 4a is formed, and a fitting groove 10 is provided so that the driver blade 6 can be fitted. The driver blade 6 is fixed to the piston 4 by a pin 5 with its mounting portion 6 a fitted in the fitting groove 10. A seal member 18 such as an O-ring that seals between the piston 4 and the cylinder 3 is provided on the outer periphery of the piston 4.

  In the cylinder 3, the compressed air that has flowed into the cylinder 3 from the pressure accumulating chamber 2 flows only in the direction of the return air chamber 14, and the lower side of the piston 4 in the cylinder 3. An air passage 17 is provided to communicate with the side and return the driver blade 6 to the top dead center. In the vicinity of the lower end of the moving stroke of the piston 4, a damper 15 made of a flexible material such as rubber for absorbing surplus energy after driving a stopper 22 such as a nail by the driver blade 6 is provided.

  At the time of driving, the upper side of the piston 4 in the cylinder 3 is pressed by the compressed air in the pressure accumulating chamber 2, so that the piston 4 rapidly moves in the direction of the bottom dead center in the cylinder 3. And since the driver blade 6 attached to the lower part of the piston 4 also moves downward, the stopper 22 is driven by the lower end portion 9b. The air under the piston 4 in the cylinder 3 flows into the return air chamber 14 through the air passage 17 as the piston 4 moves downward, and the piston 4 passes through the air passage 13 provided in the cylinder 3. The compressed air above the piston 4 in the cylinder 3 also flows into the return air chamber 14. Excess energy of the driver blade 6 after driving the stopper 22 is absorbed by the piston 4 deflecting the damper 15. When the compressed air on the upper side of the piston 4 in the cylinder 3 is exhausted, the lower side of the piston 4 in the cylinder 3 is pressed by the compressed air accumulated in the return air chamber 14 so that the piston 4 and the driver blade 6 are at top dead center. Return to the position.

  At the time of driving operation, the driver blade 6 integrally coupled with the piston 4 by the action of compressed air moves suddenly in the direction of the bottom dead center in the cylinder 3, and as a reaction, the main body of the driving machine 1 moves upward. . In order to reduce the reaction of the driving machine main body, the piston 4 is generally made of a light metal having a small specific gravity, and the driver blade 6 is generally made of a high-strength material such as iron in order to hit a nail. Those dimensions are appropriately set so that the largest of the used fasteners 22 can be hit.

  FIG. 2 is a perspective view of the piston 4 of the driving machine. The piston 4 is manufactured from a light metal such as aluminum, and a boss 4a is integrally formed below the boss 4a. A fitting groove 10 is provided on the boss 4a so that the driver blade 6 can be fitted. Further, a hole 12 for inserting a pin for fixing the driver blade 6 is formed in the boss 4 a in the vertical direction with respect to the driver blade 6 fitted in the fitting groove 10.

  As shown in FIGS. 3 and 4, the mounting portion 6a of the driver blade 6 that fits in the fitting groove 10 of the piston 4 has a plate-like shape of a substantially rectangular plane, and an elliptical oblong hole in the vicinity of the center thereof. 7 is formed. The mounting portion 6a of the driver blade 6 is fitted in the fitting groove 10, positioned so that the bottom portion 10a of the fitting groove 10 and the tip of the driver blade 6 abut, and penetrates the long hole 7 provided in the driver blade 6. Thus, the pin 5 is press-fitted and fixed in the hole 11 having a circular cross section provided in the boss 4a. At this time, as can be understood from FIG. 4, the positions of the hole 12 and the long hole 7 are determined so that the pin 5 contacts the upper part of the elliptical long hole 7 of the driver blade 6. As a result, after the driver blade 6 is attached to the piston 4, the lower portion of the pin 5 is fixed so as not to contact the elongated hole 7 of the driver blade 6. Furthermore, it has a structure in which an arc 8 having apexes in the direction of the long hole 7 is formed at both ends in the width direction of the mounting portion 6a of the driver blade 6. The length of the long hole 7 in the longitudinal direction is preferably 10% or more larger than the length in the short direction, particularly preferably 50% or more. However, the effect of the present invention can be obtained if there is an amount that exceeds a substantial design tolerance or manufacturing tolerance (for example, 1%). By increasing the size of the hole in this manner, the excessive load in the driving direction generated during the blanking operation is distributed without being concentrated in one place of the long hole 7 of the driver blade 6. The stress generated at the edge can be effectively dispersed, and the durability of the driver blade can be improved.

  The shape of the driver blade 6 will be further described. FIGS. 5A and 5B are front views showing a part of the driver blade 6. In FIG. 5, the width direction and the vertical direction are defined as shown for convenience of explanation.

  In FIG. 5, the attachment portion 6a of the driver blade 6 has a substantially square basic shape, and an elliptical ellipse 7 is formed slightly below the center. The position of the pin 11 with respect to the elongated hole 7 is indicated by a circle indicated by a dotted line in FIG. 5A. As is clear from the drawing, there is a large gap below the circle indicated by a dotted line, and the driver blade 6 The center point of the long hole 7 is positioned below the center point of the pin. Further, curved portions that are arcs 8 are formed on both sides of the attachment portion 6a in the width direction. As a result, as shown in FIG. 5 (2), the width 51 near the upper end of the mounting portion 6a and the width 53 near the lower end are almost the same, but in the vicinity of the center (or the center of the pin). The width 52 is narrower than the widths 51 and 53. The effect of the present invention can be obtained even if the both sides in the width direction of the mounting portion 6a are not curved, but the effect of the present invention can be obtained. However, by forming the curved arc 8, the surplus load in the driving direction generated during idle driving can be obtained. Since the effect of dispersing without increasing the concentration in one place of the long hole 7 of the driver blade 6 is increased, the stress generated at the edge of the long hole 7 can be effectively dispersed, and the durability of the driver blade is further improved. can do. Further, by making the shape of the hole of the driver blade an ellipse instead of a perfect circle and forming a curved portion, the driver blade 6 can be reduced in weight as compared with the conventional example. The reaction force generated during operation can be reduced.

FIG. 6 is a partial front view of a driver blade 6 in another embodiment, and FIGS. 7A and 7B are views for explaining the shape of a long hole of the driver blade 6. In FIG. 6, the long hole 7a has a shape in which two semicircles are connected by a straight line, that is, an oval circle. It is important is to have the top of the long hole 7, as shown in FIG. 7 (2) is approximately the shape of the same outer diameter as the pin 5 so as to be in contact with the upper half of the pin 5. Therefore, when the pin 5 is a perfect circle, the upper part of the long hole 7 is a corresponding perfect circle. If the long hole 7 is an ellipse as shown in FIG. 7 (1), the pin 5 may be a perfect circle or an ellipse having a shape close to the shape of the upper part of the long hole 7. After the driver blade 6 is attached to the piston 4, it is preferable that the gap with the pin 5 at the upper part of the long hole 7 is preferably designed to be almost zero, but the intention is to exclude even gaps and tolerances necessary for assembly However, there may of course be gaps necessary for assembly. Also in FIG. 6, as in the example of FIG. 5, the center point of the long hole 7a of the driver blade 6 is positioned below the center point of the pin.

Further, it is important that all or most of the middle portion of the long hole 7 and all the lower portion of the long hole 7 do not contact the pin 5 . Although the shape of the intermediate portion is substantially parallel in FIG. 7 (2), the intermediate portion may have a gently curved shape like a long hole 7 shown in FIG. 7 (1). Furthermore, the shape of the lower portion of the long hole 7 has a relatively high degree of freedom and may be any smooth shape.

  According to the long hole 7a shown in FIG. 7 (2), the force concentrated on the portion 25 shown in FIG. 10 (5) is applied to the entire middle part of the long hole 7a. The destruction phenomenon of the blade 6 can be effectively avoided, and the driver blade 6 having the same thickness, the same material, and the same outer shape is realized as compared with the conventional shape shown in FIG. can do. Further, as shown in FIGS. 7 (1) and 7 (2), since the radius of curvature of the intermediate portion is larger than the radius of curvature of the upper portion, the effect of dispersing local stress generation is enhanced.

  As described above, according to the present invention, it is possible to disperse the stress generated at the edge of the long hole 7 of the driver blade 6 even when a relatively soft wood or a driving operation is performed without noticing that there is no fastener. It is possible to improve the durability of the driver blade and realize a driving machine with a small reaction when driving the stopper.

  Furthermore, according to the present invention, since the above effect is realized by improving only the shape of the driver blade, a driving machine that is inexpensive and has good assemblability can be realized.

  As described above, the present invention has been specifically described based on the embodiment. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

  For example, in the present embodiment, an example in which the present invention is applied to a pneumatic driving machine has been described. However, the present invention is not limited to a pneumatic driving machine, and can also be applied to electric and combustion driving machines.

The fragmentary sectional view of the driving machine which shows one Embodiment of this invention. The perspective view of piston 4 of the driving machine of FIG. Sectional drawing which shows the attachment structure of piston 4 and driver blade 6 of the driving machine of FIG. FIG. 4 is another cross-sectional view showing a cross section of the AA portion of FIG. 3. The front view which shows a part of driver blade 6 of the driving machine of FIG. The front view which shows a part of driver blade 6 concerning another embodiment. (1) is a figure for demonstrating the shape of the long hole 7 of the driver blade 6 of FIG. 5, (2) is a figure for demonstrating the shape of the long hole 7a of the driver blade 6 of FIG. Sectional drawing which shows the attachment structure of the piston and driver blade in the conventional driving machine. FIG. 9 is another cross-sectional view showing a cross section of the BB portion in FIG. 8. The conceptual diagram for demonstrating the force concerning piston 4, driver blade 6, stopper 22, and pin 5 at the time of driving operation of a driving machine

Explanation of symbols

1: Driving machine 2: Pressure accumulating chamber 3: Cylinder 4: Piston 4a: Boss (of piston) 5: Pin 6: Driver blade 6a: Mounting portion (of driver blade) 7, 7a: Long hole
8: Arc portion 9a: Upper end portion (of driver blade) 9b: Lower end portion (of driver blade) 10: Fitting groove
10a: bottom surface (of fitting groove) 11: hole (of boss)
12: Hole of driver blade 13: Air passage 14: Return air chamber 15: Damper 16: Check valve 17: Air passage 18: Seal member 22: Stopper 26: Crack 51: Width near upper end 52: Center Width near the edge 53: Width near the lower edge

Claims (8)

A pressure accumulating chamber that stores compressed air, a cylinder that can communicate with the pressure accumulating chamber, a piston that reciprocates up and down in the cylinder, and a groove that is inserted upward from the bottom of the piston and fixed by a pin. It has a driver blade that, said fastener by the compressed air stored in the pressure accumulation chamber the piston is driven by supplying into the cylinder, said driver blade fixed to said piston pushes the stopper In a driving machine for driving
Inserted so that the upper end of the driver blade abuts the bottom of the groove,
The hole formed in the driver blade through which the pin passes is formed in a shape larger than the diameter of the pin , long in the moving direction of the piston, and short in the direction perpendicular to the moving direction,
The driving machine is characterized in that the driver blade is fixed to the piston so that an upper part of the pin is in contact with the driver blade and a lower part of the pin is not in contact with the driver blade . The holes, fastener driving tool according to claim 1, characterized in that a moving direction of the piston is an ellipse having a long radius. 2. The driving machine according to claim 1 , wherein the shape of the hole is an oval shape in which two semicircles are connected by a straight line. The holes, fastener driving tool according to claim 2 or 3 moving direction of the length of the piston being greater than 10% than the diameter of the pin. A boss protruding downward is formed at the lower part of the piston, and a groove for inserting the driver blade is formed upward from the lower end of the boss on the boss.
To the boss, the driving machine of claim 4, wherein the hole for inserting the pin is formed laterally across the groove. The shape of the attachment portion of the driver blade to the piston is a substantially rectangular plate shape, and has an arcuate outline inward on one side or both sides of the side, and in the vicinity of the central portion in the vertical direction of the attachment portion. The driving machine according to claim 5 , wherein a width is narrower than a width at an end portion in the vertical direction of the mounting portion. The shape of the attachment portion of the driver blade to the piston is a substantially square plate shape, and an arc-shaped notch having a vertex in the hole direction is formed on one side or both sides of the side. The driving machine according to claim 5 . A pressure accumulating chamber for storing compressed air, a cylinder that can communicate with the pressure accumulating chamber, a piston that reciprocates up and down in the cylinder, and a boss that protrudes downward at the bottom of the piston are formed. grooves are formed upward from the lower end, has a driver blade which is fixed by penetrating the inserted pin from the through hole formed on the side of the boss, the compressed air stored in the pressure accumulation chamber in the said piston driving by supplying into the cylinder, driving machine implanting the fastener to be nailed by said driver blade fixed to said piston pushes the stopper,
Before Kido driver holes the pin formed on the blade is penetrated, long in the moving direction of the piston a has size shape than the through hole formed on the side of the boss, the moving direction and the vertical A short shape in the direction,
The center of the bore of said driver blade, than the circumferential center of the pin of the cylindrical or cylindrical and located below the top of the pin is in contact with the driver blade, the lower portion of the pin and the driver blade The driving machine is characterized in that the driver blade is fixed to the boss so as not to contact.

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