Shock Absorption Device for Pneumatic Tool

Abstract

A device absorbs shock in a pneumatic tool containing a body, a cylinder, a valve unit, a piston member, plural buffer springs, and multiple fitting sleeves. The body includes a grip and a fitting sleeve fitted with the grip. The fitting sleeve has a chamber, a close face formed on a first end thereof, and an opening formed on a second end thereof. Each fitting sleeve is hollow and includes a limitation length forming along a hollow extending direction and shorter than a largest length. Multiple positioning sleeves are defined between a close face of the fitting sleeve and an abutting portion of the cylinder, and the multiple positioning sleeves are hollow so as to accommodate plural buffer springs. Because the limitation length is shorter than the largest length, the plural buffer springs extend out of the multiple positioning sleeves respectively.

Claims

1. A shock absorption device for a pneumatic tool, wherein a pneumatic tool comprises: a body including a grip and a fitting sleeve fitted with the grip, with the fitting sleeve having a chamber defined therein, a close face formed on a first end thereof, and an opening formed on a second end thereof; a cylinder slidably fixed in the chamber of the fitting sleeve and a part thereof extending out of the opening of the fitting sleeve, with the cylinder including a room defined therein and an abutting portion adjacent to the close face of the chamber of the fitting sleeve; a valve unit fixed between the room and the abutting portion of the cylinder; a piston member accommodated in the room of the body and sliding forward and backward along a movement axis; plural buffer springs mounted in the chamber of the fitting sleeve and abutting against the close face of the chamber of the fitting sleeve and the abutting portion of the cylinder, wherein a pressing direction of each buffer spring is parallel to the movement axis of the piston member, and plural elastic supporting points form between the close face and the abutting portion so that when the plural buffer springs do not press, a largest length forms; and multiple positioning sleeves is hollow and includes a limitation length forms along a hollow extending direction, the limitation length is shorter than the largest length, the multiple positioning sleeves are defined between the close face of the chamber of the fitting sleeve and the abutting portion of the sliding sleeve of the cylinder, and the multiple positioning sleeves are hollow so as to accommodate the plural buffer springs; hence the limitation length is shorter than the largest length, the plural buffer springs extend out of the multiple positioning sleeves respectively.

2. The shock absorption device for the pneumatic tool as claimed in claim 1, wherein a stop rib extends inwardly from a peripheral side of the opening, and the cylinder is stopped by the stop rib of the fitting sleeve for matching with a washer.

3. The shock absorption device for the pneumatic tool as claimed in claim 1, wherein the cylinder includes a sliding sleeve and a base, wherein the sliding sleeve is slidably fitted in the chamber of the fitting sleeve, and the sliding sleeve has a hollow portion formed therein, wherein the abutting portion of the cylinder is fixed on one end of the hollow portion adjacent to the close face of the chamber of the fitting sleeve, and one end of the base is inserted into the hollow portion of the sliding sleeve and is connected with the sliding sleeve in a screwing manner.

4. The shock absorption device for the pneumatic tool as claimed in claim 3, wherein the sliding sleeve has a limiting slot defined on an outer side thereof to insert a defining element of the fitting sleeve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a perspective view showing the assembly of a pneumatic tool according to a preferred embodiment of the present invention.

[0015] FIG. 2 is a perspective view showing the exploded components of the pneumatic tool according to the preferred embodiment of the present invention.

[0016] FIG. 3 is a cross sectional view showing the assembly of the pneumatic tool according to the preferred embodiment of the present invention.

[0017] FIG. 4 is a cross sectional view taken along the line A-A of FIG. 3 according to the preferred embodiment of the present invention.

[0018] FIG. 5 is an amplified cross sectional view of a portion B of FIG. 3.

[0019] FIG. 6 is a cross sectional view showing the operation of the pneumatic tool according to the preferred embodiment of the present invention.

[0020] FIG. 7 is another cross sectional view showing the operation of the pneumatic tool according to the preferred embodiment of the present invention.

[0021] FIG. 8 is also another cross sectional view showing the operation of the pneumatic tool according to the preferred embodiment of the present invention.

[0022] FIG. 9 is an amplified cross sectional view of a portion C of FIG. 8.

[0023] FIG. 10 is a cross sectional view of a conventional pneumatic tool.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention will be clearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustration only, preferred embodiments in accordance with the present invention.

[0025] FIGS. 1 to 5 show a shock absorption device for a pneumatic tool according to a preferred embodiment of the present invention. The pneumatic tool comprises: a body 1, a cylinder 2, a valve unit 3, a piston member 4, plural buffer springs 5, and multiple positioning sleeves 6. The body 1 includes a grip 11 and a fitting sleeve 12 fitted with the grip 11. The grip 11 has an air inlet segment 111, an air passage 112 communicating with the air inlet segment 111, and a control switch (not shown) for controlling air to flow into the air inlet segment 111. The fitting sleeve 12 has a chamber 120 defined therein, a close face 121 formed on a first end thereof, an opening 122 formed on a second end thereof, and a stop rib 124 extending inwardly from a peripheral side of the opening 122.

[0026] The cylinder 2 includes a sliding sleeve 21 and a base 22, wherein the sliding sleeve 21 is slidably fitted in the chamber 120 of the fitting sleeve 12, and the sliding sleeve 21 has a hollow portion 210 formed therein, an abutting portion 211 adjacent to the close face 121 of the chamber 120 of the fitting sleeve 12. The sliding sleeve 21 is stopped by a washer 125 for matching with the stop rib 124 of the fitting sleeve 12, and the sliding sleeve 21 has a limiting slot 213 defined on an outer side thereof to insert a defining element 126 of the fitting sleeve 12, wherein one end of the base 22 is inserted into the hollow portion 210 of the sliding sleeve 21 and is connected with the sliding sleeve 21 in a screwing manner, a part of the base 22 extends out of the opening 122 of the chamber 120 of the fitting sleeve 12, and the base 22 has a room 220 defined therein, the room 220 has an expanding groove 221 formed on a rear end thereof, the expanding groove 221 has a circular moving element 222 and a compression spring 223.

[0027] The valve unit 3 is fixed between the room 220 and the abutting portion 211 of the cylinder 2, such that high pressure air flows toward the valve unit 3 via the air passage 112 of the grip 11.

[0028] The piston member 4 is accommodated in the room 220 of the base 22 and slides forward and backward along a movement axis 41.

[0029] The plural buffer springs 5 are circularly mounted in the chamber 120 of the fitting sleeve 12 and abut against the close face 121 of the chamber 120 of the fitting sleeve 12 and the abutting portion 211 of the sliding sleeve 21 of the cylinder 2, wherein a pressing direction of each buffer spring 5 is parallel to the movement axis 41 of the piston member 4, and plural elastic supporting points form between the close face 121 and the abutting portion 211 so that when the plural buffer springs 5 do not press, a largest length 5A forms.

[0030] Each of the multiple positioning sleeves 6 is hollow and includes a limitation length 6A forms along a hollow extending direction, wherein the limitation length 6A is shorter than the largest length 5A, the multiple positioning sleeves 6 are defined between the close face 121 of the chamber 120 of the fitting sleeve 12 and the abutting portion 211 of the sliding sleeve 21 of the cylinder 2, and the multiple positioning sleeves 6 are hollow so as to accommodate the plural buffer springs 5. Because the limitation length 6A is shorter than the largest length 5A, the plural buffer springs 5 extend out of the multiple positioning sleeves 6 respectively so that the multiple positioning sleeves 6 separate and fix the plural buffer springs 5 individually.

[0031] After the control switch on the grip 11, as shown in FIGS. 5 and 6, is turned on, the high pressure air flows into the valve unit 3 through the air passage 112 of the grip 11. Then the high pressure air flows into the room 220 of the base 22 from the valve unit 3 to push the piston member 4 to slide toward a front end of the room 220, such that a tool head (not shown) is hit by the piston member 4, and the piston member 4 is stopped by the tool head, as shown in FIGS. 7 and 8. Thereafter the high pressure air flows into the room 220 of the cylinder 2 through the valve unit 3 to push the piston member 4 to move toward a rear end of the room 220. Then the piston member 4 hits the valve unit 3 so that the cylinder 2 is driven to move backward. The plural buffer springs 5 are biased against the close face 121 of the chamber 120 of the fitting sleeve 12 and the abutting portion 211 of the sliding sleeve 21 of the cylinder 2 to disperse and to buffer a reaction force, thus absorbing shock. When the cylinder 2 moves backward to impact the plural buffer springs 5, the plural buffer springs 5 press the multiple positioning sleeves 6 at the limitation length 6A, the multiple positioning sleeves 6 limit the plural buffer springs 5 to be pressed respectively so as to prolong service life of the plural buffer springs 5 and to reduce the reaction force to pass toward the user's hand and to push the piston member 4 forward and backward

[0032] Accordingly, the shock absorption device of the present invention has advantages as follows:

[0033] The shock absorption device of the present invention contains the plural buffer springs 5 which are accommodated in the chamber 120 of the fitting sleeve 12, and the plural buffer springs 5 extend out of the multiple positioning sleeves 6 respectively so that the multiple positioning sleeves 6 separate and fix the plural buffer springs 5 individually to scatter and to buffer reaction force evenly, thus having multiple shock absorption. When the plural buffer springs 5 press the multiple positioning sleeves 6 at the limitation length 6A individually, the multiple positioning sleeves 6 limit the plural buffer springs 5 to be pressed continuously so as to avoid excessive compression of the plural buffer springs 5, thus prolonging service life of the plural buffer springs 5. Preferably, the plural buffer springs 5 buffer the reaction force, such that the shock is absorbed and the reaction force which passes to the user's hand is reduced, thus operating the pneumatic tool easily and protecting the user's wrist.

[0034] While various embodiments in accordance with the present invention have been shown and described, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.