JP4379123B2 - Impact tool - Google Patents

Description

  The present invention relates to a striking tool provided with a mechanism for preventing a continuous striking motion (hereinafter referred to as idle driving) of a striking element when no load is applied.

  The rotational force of the motor is converted into a reciprocating motion, the piston provided in the cylinder is reciprocated, the striking element is interlocked via the air chamber in the cylinder, and the end of the tip tool detachably held in the cylinder; In a striking tool having a striking transmission mechanism that transmits striking to a tip tool by striking a contactable meson, the striking tool is held movably in the axial direction of the cylinder, and the meson is always attached to the tip tool side. When the meson is moved to the piston side by a predetermined amount or more, the breathing hole is blocked, and when the meson is moved to the tip tool side or more by a predetermined amount, the idle punching mechanism has a slide sleeve that opens the breathing hole. One example of a conventional striking tool in which is used is disclosed in Patent Document 1.

  The idle driving prevention mechanism includes an engaging portion that engages with the slide sleeve on the outer periphery in the vicinity of the end portion on the striker side of the intermediate member, and an elongated hole that has a size larger than the axial movement amount of the intermediate member on the outer periphery of the cylinder. And an annular portion having an inner diameter portion that engages with the engaging portion and a protruding portion that protrudes from the elongated hole of the cylinder to the outer periphery of the cylinder, and is held on the outer periphery of the slide sleeve so as to be movable in the axial direction of the cylinder. Is configured to have a slide portion that engages with the protrusion on the anti-tip tool side and the other end is urged to the tip tool side by the urging means, whereby the intermediate element is struck by the striker. Since the portion is held by the annular member, it is possible to suppress the occurrence of shake of the meson in the radial direction when the meson reciprocates.

Japanese Patent Laid-Open No. 2003-212370

  In the conventional hitting tool described above, the annular member has a shape having a protruding portion, and the protruding portion protrudes from the outer diameter of the cylinder, and the annular member cannot be inserted into the cylinder from the tip tool axis direction. Then, it was assembled by inserting it into the cylinder long hole from the cylinder outer direction and further rotating the annular member by 90 ° around the protrusion.

  For this reason, it is necessary to make the axial dimension of the annular member smaller than the circumferential dimension of the cylinder elongated hole, and it is impossible to increase the axial dimension of the annular member and improve the strength of the annular member. there were. Further, when the circumferential dimension of the cylinder slot is increased in order to increase the axial dimension of the annular member, the strength of the cylinder cannot be improved.

  Further, the work of rotating the annular member by 90 ° around the protrusion in the cylinder is poor in workability and assemblability.

  An object of the present invention is to provide a striking tool that can eliminate the above-mentioned conventional drawbacks and can improve the life and assembly.

  The above-mentioned purpose is to be located in a long hole having a dimension larger than the axial movement amount of the mesonment on the outer circumference of the cylinder, a locking member that contacts the slide sleeve on the outer circumference of the cylinder, and a step portion located on the striker side of the meson This can be achieved by providing an annular member located on the outer periphery and having an engaging portion with the locking member.

  According to the present invention, the locking member positioned on the outer periphery of the cylinder in a long hole having a dimension larger than the axial movement amount of the meson, and contacting the slide sleeve on the outer periphery of the cylinder, and the step positioned on the striker side of the meson By providing an annular member located on the outer periphery of the part and having an engaging part with the locking member, the axial dimension of the annular member can be made larger than the cylinder slot, and the annular member and the cylinder It is possible to provide a striking tool that can ensure the strength and improve the life.

  Further, the annular member can be assembled simply by inserting the locking member into the engaging portion provided in the annular member from the cylinder long hole, and the assemblability can be improved.

  An embodiment of an impact tool according to the present invention will be described below with reference to FIGS. 1 and 2.

  First, operation | movement of the impact tool in this embodiment is demonstrated.

  The rotational force of the motor 13 rotates the crankshaft 15 through the first gear 14 and is converted into a reciprocating motion of the piston 17 by the connecting rod 16. A substantially sealed air chamber 18 is formed between the piston 17 in the cylinder 4 and the striker 3, and the pressure of the air chamber 18 fluctuates due to the reciprocating motion of the piston 17, and the striker 3 strikes the intermediate member 2. The striking motion is transmitted to the tip tool 1.

  The intermediate part 2 is formed with a smaller diameter in the cylindrical part 2b closer to the impactor 3 than in the cylindrical part 2a closer to the tip tool 1, and the intermediate part 2b is closer to the cylindrical part 2b closer to the impactor 3. A washer A 10, a damper 11, and a washer B 12 are fixed to the outer peripheral position by a C ring 19.

  When the meson 2 moves to the striker 3 side, the stepped portion 2c facing the striker 3 between the cylindrical portion 2a and the cylindrical portion 2b where the diameter of the meson 2 is changed comes into contact with the washer A10. The shock when the intermediate element 2 moves to the striker 3 side is buffered by the damper 11 which is a shock absorbing member via. Further, the amount of movement of the intermediate element 2 toward the striker 3 is regulated by the contact between the step 2c and the washer A10.

  The engagement portion 2d on the outer periphery of the end of the striker 3 on the side of the intermediate member 2 has a smaller outer diameter than the small diameter portion 2b and extends in parallel with the axial direction of the cylinder 4, and an inner diameter portion that engages with the engagement portion 2d, and An annular member 6 having an outer diameter portion that engages with the inner diameter portion of the cylinder 4 and a stepped portion 2e that faces the striker 3 side between the engagement portion 2d and a cylindrical portion 2b that changes the diameter of the intermediate element 2 is disposed. is doing.

  As shown in FIG. 2, the outer diameter portion that engages with the inner diameter portion of the cylinder 4 of the annular member 6 is provided with hole portions 6 a that are engaging portions (two locations in the figure). A pin 5 that is a locking member that engages with the engaging portion 6a is disposed. The hole diameter of the hole portion 6a that is the engaging portion is set to be slightly larger than the outer diameter of the pin 5 that is the locking member so that the pin 5 that is the locking member can be inserted. It is set slightly smaller than the outer circumferential direction dimension of the long hole 4a. The locking member 5 engages with a longitudinally long slot 4a in the tool axis direction provided in the cylinder 4, and the locking member 5 moves in the axial direction along the slot 4a. The long hole 4a has a dimension longer than the amount of movement of the meson 2 in the longitudinal direction of the tool axis.

  A slide slide sleeve A 7 and a slide sleeve B 8 are provided on the outer periphery of the cylinder 4. The slide sleeve B8 contacts the locking member 5, and the slide sleeve A7 contacts the slide sleeve B8. The slide sleeve A7 is urged in the direction of the tip tool 1 by the spring 9, and the slide sleeve B8, the annular member 6, and the intermediate element 2 are similarly urged in the direction of the tip tool 1.

  The state shown in FIG. 1 is an impact, and when the tip tool 1 is pressed against the work material, the piston 17 resists spring pressure against the meson 2, ring member 6, locking member 5, slide sleeve B8, and slide sleeve A7. Move in the direction.

  Further, in the above-described embodiment, the slide sleeve is constituted by two members, the slide sleeve A7 and the slide sleeve B8, but these may be constituted by one member.

  Moreover, the above-described idle hitting prevention device portion of the hitting tool of the present invention is assembled by the following procedure.

  First, the intermediate element 2, the washer A 10, the damper 11 and the washer B are inserted into the cylinder 4, and the C ring 19 is fitted into the inner circumferential groove of the cylinder 4. Next, the annular member 6 is inserted into the cylinder 4, and the inner diameter portion of the annular member 6 and the engaging portion 2 d of the intermediate element 2 are engaged.

  The slide slide sleeve A7 and the slide sleeve B8 are inserted into the outer periphery of the cylinder 4, and the slide slide sleeve A7 and the slide sleeve B8 are moved to the piston 17 side until the long hole 4a of the cylinder 4 is not hidden by the slide sleeve B8.

  Thereafter, the pin 5 as the locking member is inserted into the hole 6a of the annular member 6 from the elongated hole 4a of the cylinder 4, and the tip of the slide slide sleeve A7 and the slide sleeve B8 is brought into contact with the pin 5 as the locking member. Move in the tool direction.

  Finally, the spring 9 is inserted into the outer periphery of the slide slide sleeve A7, and the slide slide sleeve A7, the slide sleeve B8, and the pin 5 are urged in the direction of the tip tool axis, whereby the intermediate member 2 is moved through the annular member 6 to the tip tool. Energize in the axial direction.

  Further, since the pin 5 as the locking member serves as the slide sleeve B8 to prevent the cylinder 4 from coming off in the outer diameter direction, the number of parts can be reduced and the assembling work can be improved.

  Thus, the assembly work of the idle hitting prevention device portion of the hitting tool of the present invention is completed.

  As described above, the hitting tool of the present invention can be assembled simply by inserting the pin 5 as the locking member into the hole 6a of the annular member 6 from the elongated hole 4a of the cylinder 4, The dimension in the axial direction of the annular member 6 can be formed larger than the dimension in the outer peripheral direction of the long hole 4a, the strength of the annular member 6 can be ensured, and the life can be improved.

  Further, the long hole 4a of the cylinder 4 may be set to a dimension in the outer circumferential direction to ensure the strength of the pin 5, and the strength of the cylinder 4 can be secured.

The longitudinal section side view showing one embodiment of the present invention impact tool. It is the sectional view on the AA line of FIG.

Explanation of symbols

1 is a tip tool, 2 is an intermediate element, 2a is a cylindrical part, 2b is a cylindrical part, 2c is a step part, 2d is an engaging part, 2e is a step part, 3 is a striker, 4 is a cylinder, 4a is a long hole 5 is a locking member, 6 is an annular member, 6a is an engaging portion, 7 is a slide sleeve A, 8 is a slide sleeve B, 9 is a spring, 10 is a washer A, 11 is a damper, 12 is a washer B, 13 Is a motor, 14 is a first gear, 15 is a crankshaft, 16 is a connecting rod, 17 is a piston, 18 is an air chamber, and 19 is a C-ring.

Claims (3)

A motor, a crankshaft that rotates by rotation of the motor, a piston that engages with the crankshaft and reciprocates in the axial direction of the cylinder, and can reciprocate in the axial direction of the cylinder in the cylinder A striking element that holds and reciprocates the piston through an air chamber in the cylinder, and is held in the cylinder so as to be reciprocable in the axial direction of the cylinder. An intermediate element capable of striking the tool end, a breathing hole for communicating the air chamber with the outside air in the cylinder, and being held so as to be movable in the axial direction of the cylinder, the intermediate element is always biased toward the tip tool side. The breathing hole is closed when the meson is moved to the piston side by a predetermined amount or more, and when the meson is moved to the tip tool side or more by a predetermined amount, the breathing hole is closed. A striking tool having a slide sleeve that opens a breathing hole, and an urging means that constantly urges the slide sleeve toward the tip tool side, and is provided on the outer periphery of the cylinder on the outer circumference of the cylinder relative to the amount of axial movement of the meson. A locking member that is located in a long hole having a large dimension and that contacts the slide sleeve on the outer periphery of the cylinder; and an outer periphery of a step portion that is positioned on the striking element side of the intermediate element, and the locking member An impact tool comprising an annular member having an engaging portion , wherein the locking sleeve prevents the locking member from coming off by contacting the locking member . 2. The batting according to claim 1, wherein the slide sleeve includes a slide sleeve A capable of sliding on the outer periphery of the breathing hole and a slide sleeve B positioned between the slide sleeve A and the locking member. tool.   A plurality of the long holes are provided at a predetermined interval in the circumferential direction, the locking member is a plurality of pins, and the engaging portion is a hole having substantially the same size as the pin outer diameter. The impact tool according to claim 1.

Images