KR102231953B1 - Safety valve for an air grinder - Google Patents

Abstract

The present invention relates to a safety valve used in an air grinder, and more particularly, a main body of an air grinder is connected to the front end side and a pneumatic hose is connected to the rear end to provide a pneumatic passage from the pneumatic hose to the air grinder. The valve mechanism is formed of a type valve body, a valve hole formed to be connected with a pneumatic passage inside the valve body, a valve rod disposed on the valve hole to open and close the pneumatic passage, and a coil spring elastically supporting the valve rod. And the end side of the valve rod passes through the body of the valve body and protrudes outward by a predetermined length, and on the outer surface of the valve body, the valve rod slides forward or backward, or is angular motion in a hinged manner. A cylindrical valve socket or link lever that selectively protrudes and protrudes from the end side is installed, and a safety ring that can be hung on the operator's wrist is connected to the valve socket or link lever, so that the valve socket is pushed forward or the link lever is leveled. When the air grinder is dropped by the operator's mistake or carelessness, the valve socket slides to the rear side or the link lever returns to the vertical direction as soon as the air grinder is suspended from the safety hook. It is a safety valve for an air grinder that is erected so that the pneumatic passage can be automatically closed, and through this, various safety accidents that occur when using the air grinder can be prevented in advance.

Description

Safety valve for an air grinder

In the present invention, when the air grinder is missed due to an operator's mistake or carelessness while performing a surface treatment work at a rather high position such as a wall structure or a ceiling structure, the air grinder is attached to the safety hook on the operator's wrist. The present invention relates to a safety valve for an air grinder that prevents various safety accidents that occur when the air grinder is used by closing the flow path of pneumatic pressure through the air grinder as soon as the grinder is suspended.

In general, grinding work that requires high precision, such as removing contaminated parts of the ship's paintwork when building a ship, trimming protruding surfaces such as steel structures beautifully, or chamfering a specific part. A grinder using a high-speed rotating grinding wheel is widely used, and the grinder can be roughly classified into an electric grinder using electric power and an air grinder using compressed air depending on the type of driving source that rotates the grinder wheel used as the grinding wheel. have.

The air grinder includes a main body to which a pneumatic hose is connected to the rear end, a driving unit disposed inside the front end of the main body to convert pneumatic pressure into rotational force, and a driving unit installed below the front end of the main body to reduce the rotational force of the driving unit to the grinder wheel. It is made by including a gearbox to be transmitted to, the grinder wheel is installed in the form of a disk having a predetermined thickness, the central portion of which is connected to the output shaft of the gearbox.

In addition, an adjustment knob in the form of a pipe is provided at the outer periphery of the rear body of the main body to control the rotational force (rotation speed) of the grinder wheel, and at one side of the gearbox, the air grinder together with the main body is firmly attached. A handle for work is additionally connected so that it can be gripped, and a safety cover is connected and installed at the bottom side of the gearbox to prevent the grinder wheel part (about 1/2 of the total) facing the operator from being exposed to the outside. have.

The air grinder as described above has the advantage of preventing the risk of electric shock or explosion because it can rotate the grinder wheel with a relatively strong force using compressed air as a driving source, whereas wall structures or ceiling structures There is a disadvantage in that the operation of the air grinder is not stopped even when the air grinder is dropped due to a mistake or carelessness of an operator while performing a surface treatment work at a rather high position, such as.

In other words, in the case of an electric grinder, it is connected to the power source by an electric plug, so if the grinder is dropped, the electric plug can be easily removed, but in the case of an air grinder, the pneumatic hose is very close to the air grinder to prevent leakage of compressed air. Because it is firmly connected, the connection state is not released even if the grinder is dropped. This means that if the air grinder comes into contact with the operator's body during the fall, a cutout by the grinder wheel rotating at high speed or In spite of frequent cutting accidents, there was virtually no way to solve them.

The present invention was conceived to solve the conventional problems as described above, and the main body of the air grinder is connected to the front end side and the pneumatic hose is connected to the rear end side to provide a pneumatic passage from the pneumatic hose to the air grinder. A valve mechanism is composed of a valve body, a valve hole formed to be connected with a pneumatic path inside the valve body, a valve rod disposed on the valve hole to open and close the pneumatic path, and a coil spring elastically supporting the valve rod. And, the end side of the valve rod passes through the body of the valve body and protrudes outward by a predetermined length, and on the outer surface of the valve body, the end of the valve rod is slid in a forward or backward direction or is angular motion in a hinged manner. A cylindrical valve socket or link lever that selectively protrudes and exits the side is installed, and a safety ring that can be hung on the operator's wrist is connected to the valve socket or link lever, so that the valve socket is pushed forward or the link lever is moved horizontally. When tilted, the pneumatic passage of the valve body is opened to enable grinding.If the air grinder is dropped by an operator's mistake or carelessness, as soon as the air grinder hangs on the safety hook, the valve socket slides to the rear or The main technical task is to provide a safety valve for air grinders that allows the link lever to be re-established in a vertical direction to automatically close the pneumatic path, and through this, various safety accidents that occur when using the air grinder can be prevented in advance. It should be.

In addition, the present invention provides an airtight means for preventing leakage of compressed air to a portion where the end side of the valve rod passes through the body of the valve body, and flows into the air grinder through the valve body from the pneumatic hose. The loss of the resulting pneumatic pressure is zero to ensure the normal operation of the air grinder, and the inner circumferential surface of the valve socket is formed into a tapered portion that inclines in the inward direction, while the end of the valve rod is rounded in a spherical shape. By forming, the valve rod part protruding from the valve body can be pushed in quickly and accurately, and a cover cap capable of selectively opening the valve hole in the body part of the valve body is installed, and a valve rod including a sealing ring It is possible to perform more quickly and easily repair or replacement work of the coil spring and maintenance work on the inside of the valve hole, and an air grinder is attached to the safety ring at the part where the safety ring is connected to the valve socket or link lever. When the entire load of the air grinder is concentrated on the safety ring due to the suspension, a temporary fixing means that automatically separates the safety ring from the valve socket or link lever is applied, so that even after the pneumatic passage is closed by the valve rod, it rotates by the residual centrifugal force. Another technical task is to provide a safety valve for an air grinder that can fundamentally block the situation in which the grinder wheel is in contact with the operator's body.

As a means for solving the above technical problems, the safety valve for an air grinder according to the first embodiment of the present invention includes a main body of the air grinder connected to the front end side and a pneumatic hose connected to the rear end side. A pipe-type valve body providing a pneumatic path to the side, a valve hole formed to be connected with the pneumatic path inside the valve body, and a valve hole that is inserted into the valve hole and protrudes outside the body of the valve body by a predetermined length. A valve rod, a cylindrical valve socket that selectively protrudes from the valve body while sliding in the front and rear directions along the outer surface of the valve body, and the valve rod is installed inside the valve hole to operate the valve rod. And a coil spring that elastically supports the valve, and a tapered portion for pushing the valve rod portion protruding to the outside of the valve body into the inside of the valve body is provided on the inner side of the tip of the valve socket, and the outside of the valve socket On the side, a safety ring for hanging on the operator's wrist is connected and installed, and when the valve socket is moved to the front side and the valve rod is pushed into the inside of the valve body, the pneumatic passage of the valve body is opened, and the valve body is opened by the safety ring. When the valve rod protrudes as the socket is pulled to the rear side, an opening/closing structure is provided in which the pneumatic passage of the valve body is closed.

In a second embodiment of the present invention, a lever bracket is assembled and installed on an outer surface of the valve body, and a link lever selectively protruding from the valve body protruding from the valve body is angular motion with the link shaft interposed therebetween. The link shaft is installed so as to pass through the end side of the link lever in the horizontal direction at an eccentric position in one direction, and the end surface of the link lever through which the link shaft passes is operated for the protruding operation of the valve rod. By forming the cam part, the pneumatic passage of the valve body is opened when the valve rod is pushed into the valve body by the operating cam part as the link lever is bent in the horizontal direction, and the link lever is pulled by the safety ring to revert to the vertical direction. When the valve rod protrudes as it is erected, the pneumatic passage of the valve body is closed. In a third embodiment, a cover cap in the shape of a stopper covering the valve hole is assembled and installed on the body side of the valve body, and the valve rod Penetrates the cover cap and protrudes to the outside of the cover cap by a predetermined length, and the link lever is connected and installed to enable angular movement while interposing the end side of the valve rod and the link shaft, thereby bending the link lever in the horizontal direction. Accordingly, when the valve rod is pulled to the outside by the link shaft, the pneumatic passage of the valve body is opened, and the link lever is pulled by the safety ring and re-established in the vertical direction. When pushed back into the valve body, the pneumatic passage is closed.

More specifically, the opening/closing structure of the pneumatic passage applied to the first and second embodiments is formed only from the lower side or the upper side of the valve hole to the inner side, while leaving the outer surface of the valve rod and a predetermined clearance gap. It is provided on the basis of a rod hole spaced apart and a through hole formed only from the lower or upper side of the rod hole to the inner side and in contact with the outer surface of the valve rod, and the pneumatic passage is the rear end of the valve body to which the pneumatic hose is connected. The inlet passage extends from the side so that the outlet of the inlet passage communicates with the valve hole, and the discharge passage extends from the front end of the valve body to which the main body of the air grinder is connected, so that the inlet of the discharge passage communicates with the rod hole. A valve head that is elastically supported by a coil spring is protruded from one end of the valve rod as a means of opening and closing the pneumatic passage, and a predetermined clearance is provided between the outer circumferential surface of the valve head and the inner circumferential surface of the valve hole. , The stepped portion between the valve hole and the rod hole provides a valve seat for seating the valve head, and a sealing ring in close contact with the valve seat is installed on the outer circumferential surface of the valve head, and the third embodiment The opening/closing structure of the pneumatic passage applied to the valve hole is an inlet passage formed only from the lower side or the upper side of the valve hole to the inner side, and a valve seat provided at a portion where the inlet passage is stepped from the valve hole, and the coil spring is a valve head. It is elastically interposed between the and the cover cap, the pneumatic passage is in communication with the valve hole, the discharge passage is characterized in that consisting of a structure in communication with the inlet passage.

On the other hand, in the fourth embodiment of the present invention, a valve hole is formed along the longitudinal direction of the valve body from the rear end of the valve body at a position corresponding to the inner upper or lower inner part of the valve body, and the pneumatic passage is pneumatic An inlet passage extending from the rear end of the valve body to which the hose is connected in parallel with the valve hole from the lower or upper portion of the valve hole, an inlet passage communicating the inner end of the inlet passage with the inner end of the valve hole, and an air grinder The main body of the valve body is connected from the front end side of the valve body to the rear inner side of the valve hole, and the discharge passage is formed through the opening and closing structure of the pneumatic passage along the valve hole from the rear end side of the valve body. The valve rod to be inserted and installed, the valve head protruding from the front end side of the valve rod, the sealing ring installed on the outer circumferential surface of the valve head, and the inner circumferential surface of the valve hole at the rear side of the valve head so that the sealing ring selectively adheres to each other. The valve seat is provided along the line, and the outer surface of the valve head including the sealing ring and the outer surface of the valve rod are spaced apart from the inner circumferential surface of the valve hole at a predetermined distance, and the coil spring is the tip of the valve hole. It is elastically interposed between the inner surface and the valve head, and a cover cap is installed at the rear end of the valve hole to cover the valve hole, and the rear end of the valve rod passes through the cover cap to the outside of the valve body by a predetermined length. And the lever bracket is connected to the rear end of the cover cap with the link lever interposed therebetween.

As an additional matter, in the first and second embodiments, an airtight structure for blocking leakage of pneumatic pressure between the through hole of the valve body and the valve rod is additionally provided, and the airtight structure is provided at the end side of the valve rod. While forming a shutter rod having a trapezoidal cross section, the through hole has a structure formed by a taper hole having a trapezoidal cross section that is in close contact with the outer surface of the shutter rod in a wedge fashion, or a shutter cap is formed protruding at the end of the valve rod, The shutter cap has a structure in which a sealing ring covering the lower circumference of the through hole is mounted on the upper side of the shutter cap, and the shutter rod and the shutter cap are detachably assembled with the valve rod, and the valve body A cover cap in the shape of a stopper that performs a cover function of the valve hole is assembled and installed, and the ends of the shutter rod and the shutter cap are formed to be rounded in a spherical surface, and the shutter cap is inwardly on the outer surface of the valve body in close contact with the shutter cap. The shutter receiving groove to be inserted is formed concave, the valve body is assembled with a cover cap that functions as a valve hole, and the coil spring is elastically interposed between the valve head and the cover cap, and the cover cap is It is characterized in that it is fastened and installed in a state in which a sealing ring is interposed along a cap hole formed to pass through the body portion of the valve body directly above or below the valve hole.

In addition, in the valve body used in the first embodiment, the rear body portion to which the pneumatic hose is connected from the front body portion connected to the main body of the air grinder is formed inwardly, and the valve rod is formed together with the valve hole. It is installed on the front body of the valve body, and a protruding jaw is formed on a stepped portion between the front body and the rear body inside the rear end of the valve socket, while the tapered portion is formed over the inner circumferential surface of the front end side of the valve socket. A stopper means is provided on the rear end side of the rear body to prevent the valve socket from being separated, and in all the above embodiments, an air grinder is suspended from the safety ring at a portion where the safety ring is connected to the valve socket or link lever. Accordingly, when the entire load of the air grinder acts on the safety ring, a temporary fixing means for automatically separating the safety ring from the valve socket or link lever is applied, and the temporary fixing means is on the outer surface of the valve socket or link lever. C-ring made of a thin wire to be connected, or a fitting pin or a "⊃"-shaped leaf spring assembled through the outer surface of the valve socket or link lever, and the safety hook is connected to the temporary fixing means. It is characterized.

According to the present invention as described above, when the valve socket is pushed to the front side or the link lever is tilted in the horizontal direction, the pneumatic passage of the valve body is opened (ON), so that the grinding operation is possible. Therefore, when the air grinder is dropped, the valve socket slides toward the rear side of the valve body as soon as the air grinder is suspended from the safety hook on the operator's wrist (the valve body is removed from the valve socket due to the load of the air grinder. It provides the effect of automatically setting the pneumatic path to the closed (OFF) state as the link lever is retracted in the vertical direction, and through this, various safety accidents such as cutouts or cutting accidents that occur when using the air grinder. It provides an effect that can prevent in advance.

In addition, by providing an airtight means that prevents compressed air from leaking into the portion where the end side of the valve rod passes through the body of the valve body without causing any hindrance to the protruding operation at the end side of the valve rod, the valve body from the pneumatic hose It provides the effect of ensuring the normal operation of the air grinder by zeroing the loss of pneumatic pressure flowing into the air grinder through the process.In particular, when the shutter rod and taper hole of trapezoidal cross section are applied as airtight means, it is frequently used like a sealing ring. It has the effect of providing an economical and reasonable sealing structure that can block the leakage of compressed air even if the consumables requiring replacement are not used.

In addition, when the inner circumferential surface of the valve socket is formed with a tapered portion that inclines in the inward direction, while the end side of the valve rod, that is, the end of the shutter rod and the shutter cap, is rounded in a spherical shape, it protrudes from the valve body. Provides the effect of quickly and accurately pushing the end side of the valve rod, and when a cover cap capable of selectively opening the valve hole is installed in the body of the valve body, the valve rod including the sealing ring and It provides the effect of performing repair or replacement work of coil spring and maintenance work on the inside of the valve hole more quickly and easily.

As an additional matter, as the air grinder is suspended from the safety hook on the operator's wrist, the safety hook automatically connects with the valve socket or link lever when the entire load of the air grinder is concentrated on the safety hook immediately after the pneumatic passage is completely closed. By applying a temporary fixing means for separating, even after the pneumatic passage is closed by the valve rod, it provides the effect of fundamentally blocking the situation in which the grinder wheel rotated by the residual centrifugal force comes into contact with the operator's body. It provides an effect that can more reliably prevent various safety accidents that may occur when using an air grinder.

On the other hand, as in the case of the fourth embodiment, when the lever bracket and link lever constituting the safety valve are disposed on the rear surface of the valve body rather than the outer circumferential surface, the gripping of the air grinder together with the adjustment knob of the air grinder (把持用) As the lever bracket and link lever can be prevented from protruding on the outer circumferential surface of the safety valve with the handle function, the gripping work of the air grinder is not disturbed by the safety valve, and through this It provides very useful effects such as securing the safety and workability of the air grinder at the same time.

1 is an external perspective view showing a state in which a safety valve according to a first embodiment of the present invention is installed in an air grinder.
Figure 2 is a side cross-sectional view showing an open (ON) state of the safety valve according to the first embodiment of the present invention.
Figure 3 is an exploded view of Figure 2;
Figure 4 is a side cross-sectional view showing a closed (OFF) state of the safety valve according to the first embodiment of the present invention.
5 and 6 are excerpts of the "A" part of FIG. 2 showing another airtight structure of the valve rod penetrating part.
Figure 7 (a) to (c) is a cross-sectional view of the main part showing the temporary fixing means of the safety hook by type.
Figure 8 is a side cross-sectional view showing a closed (OFF) state of the safety valve according to the second embodiment of the present invention.
Fig. 9 is a rear view of the main part of Fig. 8;
10 is a side cross-sectional view showing an open (ON) state of a safety valve according to a second embodiment of the present invention.
11 is a side cross-sectional view showing a closed (OFF) state of a safety valve according to a third embodiment of the present invention.
12 is a rear cross-sectional view of the main part of FIG.
13 is a side cross-sectional view showing an open (ON) state of a safety valve according to a third embodiment of the present invention.
14 is a side cross-sectional view showing a safety valve according to a fourth embodiment of the present invention.
Fig. 15 is a rear view of Fig. 14;
16A and 16B are a side cross-sectional view and a top cross-sectional view showing a pneumatic passage structure of a valve body used in the fourth embodiment of the present invention.
17A and 17B are cross-sectional top views showing an open (ON) state and a closed (OFF) state of a safety valve according to a fourth embodiment of the present invention.

Hereinafter, the present invention for achieving the above object will be described in detail with reference to the accompanying drawings.

First, the air grinder 1 to which the safety valve 10 according to the present invention is applied, as shown in FIG. 1, includes a main body 2 to which a pneumatic hose 8 is connected to the rear end side, and the main body A driving unit (not shown) disposed inside the tip of (2) to convert pneumatic pressure into rotational force, and a gearbox 3 installed below the tip of the main body 2 to transmit rotational force of the driving unit to the grinder wheel 4 ), and the grinder wheel 4 has a disk shape having a predetermined thickness, and its central portion is connected to the output shaft of the gearbox 3 and installed.

In addition, a pipe-shaped adjustment knob 7 is provided at the outer periphery of the rear body of the main body 2 to control the rotational force (rotation speed) of the grinder wheel 4, and the gearbox 3 ) On one side (left side of the drawing) is additionally connected to the main body (2) and the handle (6) for work so that the air grinder (1) can be firmly gripped. On the lower side, a safety cover 5 is connected and installed to prevent the part of the grinder wheel 4 (a semicircle corresponding to about half of the total) from being exposed to the outside in a position facing the operator.

1 is only a representative example of an air grinder 1 to which the safety valve 10 of the present invention can be applied, and the safety valve 10 of the present invention is also used in an air grinder having a form different from that shown in FIG. ) Can be applied, and the safety valve 10 according to the present invention can be applied to an air cutter installed with a circular saw blade in place of the grinder wheel 4 or other air tools of a similar type. This is to be stated in advance.

In the safety valve 10 according to the first embodiment of the present invention, the main body 2 of the air grinder 1 is connected to the front end side, and the pneumatic hose 8 is A pipe-type valve body 11 connected to the rear end and providing a pneumatic path from the pneumatic hose 8 to the air grinder 1, and a valve hole formed to be connected with the pneumatic path inside the valve body 11 (17), a valve rod (12), which is inserted into the inside of the valve hole (17), while the lower end passes through the body of the valve body (11) and protrudes to the outside by a predetermined length, and the valve body (11). ) Is made by including a cylindrical valve socket 13 as a basic component that selectively protrudes from the lower end of the valve rod 12 protruding from the valve body 11 while sliding in the front and rear directions along the outer surface thereof.

In addition, the inside of the valve hole 17 is provided with a coil spring 16 elastically supporting the lower end of the valve rod 12, and a valve body ( A tapered portion (inclined surface) 13a is provided to push the lower end side of the valve rod 12 protruding outward of 11) into the inside of the valve body 11, and the outer surface of the valve socket 13 A safety hook (20) for hanging on the operator's wrist is connected and installed, and when the valve socket (13) is moved to the front side and the lower end of the valve rod (12) is pushed into the inside of the valve body (11), the valve body When the pneumatic passage of (11) is opened and the lower end of the valve rod 12 protrudes as the valve socket 13 is pulled to the rear by the safety ring 20, the pneumatic passage of the valve body 11 is closed. An opening and closing structure is provided.

In the drawing, a screw-type fastening part 11c for connecting the air grinder 1 and the pneumatic hose 8 is provided over the outer circumferential surface of the front end and the inner circumference of the rear end of the valve body 11, and the pneumatic hose 8 Is shown to be connected and installed with the valve body 11 by a hose connector 9, but the method of connecting the air grinder 1 and the pneumatic hose 8 with the valve body 11 is various in addition to the method shown in the drawing. The method can be applied, and it is preferable to apply an airtight means such as a sealing ring to the part connecting the air grinder (1) and the pneumatic hose (8) to the valve body (11), and provided inside the valve body (11). The opening and closing structure of the pneumatic passage can also be applied to various opening and closing structures used for various valves.

As a representative embodiment of the pneumatic passage opening and closing structure, a rod hole 18 formed from the bottom of the valve hole 17 to the inner side and spaced apart from the outer surface of the valve rod 12 at a predetermined clearance interval, and the The valve rod 12 is inserted along the through hole 18b (see Fig. 5) that is formed only from the lower portion of the rod hole 18 to the inner side and contacts the lower outer surface of the valve rod 12. The upper end of the valve rod 12 is formed by protruding a valve head 12a that is elastically supported by a coil spring 16.

Accordingly, the stepped portion between the valve hole 17 and the rod hole 18 provides a valve seat 17a for seating the valve head 12a, and the lower side of the valve head 12a is provided with a valve A sealing ring 14 in close contact with the seat 17a is installed, a predetermined clearance is provided between the outer circumferential surface of the valve head 12a and the inner circumferential surface of the valve hole 17, and the pneumatic passage is a pneumatic hose 8 The inlet passage 19 extends from the rear end of the valve body 11 to which) is connected, so that the outlet of the inlet passage 19 communicates with the valve hole 17, and the main body 2 of the air grinder 1 The discharge passage 19a extends from the front end side of the valve body 11 to which) is connected, so that the inlet of the discharge passage 19a communicates with the rod hole 18.

Since the safety valve 10 according to the present invention selectively protrudes and protrudes to the outside by a predetermined length through the body portion of the valve body 11, the lower end of the valve rod 12 selectively protrudes and opens and closes the pneumatic passage. , A fine gap is inevitably generated between the lower end of the valve rod 12 and the through hole 18b of the valve body 11, but when the safety valve 10 is opened (ON) as shown in FIG. Since the inner circumferential surface of the valve socket 13 additionally covers the through hole 18b from the bottom, the amount of compressed air leaking through the gap becomes a level that does not interfere with the operation of the air grinder 1.

Nevertheless, by applying an appropriate airtight means to the portion where the valve rod 12 passes through the valve body 11, the leakage of compressed air through the penetrating portion of the valve rod 12 is completely blocked. On the other hand, it is preferable to further secure an appropriate gap between the lower end of the valve rod 12 and the through hole 18b so that the lower end of the valve rod 12 is smoother and more accurately performed.

To this end, in FIGS. 2 to 4, the lower end of the valve rod 12 is formed with a shutter rod 12c having a trapezoidal cross section, and the through hole 18b is formed with the outer surface of the shutter rod 12c. An airtight structure formed by a taper hole 18a of a trapezoidal cross section that is closely attached in a wedge-like manner is presented, and in Figs. 5 and 6, a shutter cap is formed at the lower end of the valve rod 12. ) (12d) is formed to protrude, and a sealing ring 14 covering the lower circumference of the through hole 18b is mounted on the upper side of the shutter cap 12d.

When the shutter rod 12c and the shutter cap 12d are applied as described above, the connecting rod 12b of a predetermined length is left under the valve head 12a, and the shutter rod 12c and the shutter cap ( 12d) is manufactured as a separate part from the connecting rod 12b, and then the shutter rod 12c and the shutter cap 12d are assembled and installed at the lower end of the connecting rod 12b in a screw-fastening manner. It is advantageous in terms of easy mounting of the rod 12, and the lower surfaces of the shutter rod 12c and the shutter cap 12d are formed to be round in a spherical shape, so that the tapered portion of the valve socket 13 ( It is desirable to enable smooth opening and closing operation of the safety valve 10 linked to 13a).

In the case of protruding the shutter cap 12d at the lower end of the valve rod 12 as described above, as shown in FIG. 5, the shutter storage groove ( By forming a concave 11d), when the safety valve 10 is opened (ON) that moves the valve socket 13 to the front side and pushes the shutter cap 12d, the shutter cap 12d is It is preferable not to protrude to the outside, and if necessary, instead of the shutter receiving groove 11d, as shown in FIG. 6, as much as the protruding width of the shutter cap 12d on the inner surface of the valve socket 13 The guide groove of may be formed over the length direction of the valve socket (13).

As described above, when a guide groove corresponding to the protruding width of the shutter cap 12d is formed over the length direction of the valve socket 13, the safety valve 10 is opened (ON) by the valve socket 13 During operation, since it requires cumbersome operation to adjust the position of the guide groove to the position of the shutter cap 12d, it is preferable to apply a method of forming the shutter housing groove 11d on the valve body 11, and the same viewpoint. In the tapered portion (13a) is formed over the entire inner circumferential surface of the front end of the valve socket 13, it is preferable to perform the opening (ON) operation of the safety valve 10 more quickly and easily.

In addition, when considering the side of performing the opening and closing operation of the safety valve 10 while the valve socket 13 slides forward and backward along the valve body 11, the front and rear movement widths of the valve socket 13 While appropriately limiting, it can be seen that it is more advantageous to prevent the valve socket 13 from coming out to the rear side along the valve body 11 than in terms of operation of the valve socket 13, and for this purpose, the valve body ( On the outer surface of the body of 11) and the inner circumferential surface of the valve socket 13, a locking-type stopper structure is additionally applied.

As a typical application example of the locking stopper structure as shown in FIGS. 2 to 4, the valve body 11 is a front body 11a connected to the main body 2 of the air grinder 1 The rear body 11b to which the pneumatic hose 8 is connected is formed only inward, and a stopper 21 for preventing the valve socket 13 from being separated is provided at the rear end side of the rear body 11b. The valve socket 13 has a protruding jaw 13b, which is hooked on the stepped portion between the front body 11a and the rear body 11b, inside the rear end of the valve socket 13.

In the drawing, the stopper 21 has a ring (for example, an elastic ring made of rubber) surrounding the rear body 11b of the valve body 11, and the rear body 11b The rear end side is shown to be provided with a mounting groove (21a) for the fitting assembly of the stopper (21), but the valve socket (13) can be prevented from coming out along the rear body (11b) of the valve body (11). It should be noted that any type of stopper means may be applied, if any, and the valve rod 12 will be installed on the front body 11a of the valve body 11 together with the valve hole 17, and the valve Inside the socket 13, through holes 13c having dimensions corresponding to the front body 11a and the rear body 11b of the valve body 11 will be formed.

As an additional matter, a cover cap 15 that performs a cover function of the valve hole 17 is assembled and installed in the valve body 11, and the cover cap 15 is a valve hole 17 As it is inserted and installed with the sealing ring 14 interposed inside the cap hole 15c formed to penetrate the body portion of the valve body 11 at the direct top of the valve body 11, when the cover cap 15 is mounted It is constructed so as not to interfere with the operation of the valve socket 13 by making the top surface the same surface as the outer surface of the valve body 11 or by allowing the top surface to enter the inside of the surface of the valve body 11.

To make it easier to mount and remove the cover cap 15 as described above, a bolt and nut type fastening part 15b is provided on the lower side of the cover cap 15 and the inner circumferential surface of the upper side of the valve hole 17. ) Are formed respectively, while a tool groove (15a) is formed on the upper surface of the cover cap (15) so that tools such as a driver can be used, and the coil spring (16) includes a valve rod (12) and a cover cap. Interposed between the (15), for stable support of the coil spring (16), the bottom surface of the cover cap (15) and the upper surface of the valve head (12a) of the valve rod (12) are uneven spring support (16a) (see Fig. 2) is provided.

And, as described above, when the air grinder 1 is dropped from a high position due to a mistake or carelessness of a worker, as described above, the safety hook 20 allows the air grinder 1 to hang on the wrist of the worker at the same time. , By the load of the air grinder 1, the valve socket 13 can run to the rear side of the valve body 11 (the upper side when the air grinder is suspended), and FIGS. 2 to 4 It is desirable to make a dimension that can be hung on the operator's wrist by using a string or band of an appropriate thickness as in the above, and then connect it to the outer surface of the valve socket 13 using a fitting bolt (20a), etc. And, reference numeral 20b is a fastening hole of the fitting bolt.

As soon as the basic function of the safety ring 20 as described above, that is, the air grinder 1 is suspended from the safety ring 20 on the wrist of the operator, the valve socket 13 is As the lower end of the valve rod 12 protrudes while sliding to the rear, the valve head 12a and the sealing ring 14 of the valve rod 12 are made to the valve of the valve hole 17 by the elastic force of the coil spring 16. By being firmly in close contact with the seat 17a, it satisfies the function of automatically setting the safety valve 10 to the OFF state, which completely closes the pneumatic passage, and additionally for a short time due to the residual centrifugal force immediately after the pneumatic passage is closed. It is required to fundamentally block the situation in which the rotating grinder wheel 4 comes into contact with the operator's body.

To this end, in the present invention, immediately after the pneumatic passage is completely closed as the air grinder 1 is suspended from the safety ring 20 on the wrist of the operator, the entire load of the air grinder 1 is applied to the safety ring 20. Temporary fixing means for automatically separating the safety hook 20 from the valve socket 13 at the point when all are concentrated were additionally applied, and representative examples of the temporary fixing means are shown in Fig. 7 (A) to (C), respectively. As described above, a C-ring 22 made of a thin wire material connected to the outer surface of the valve socket 13 or a fitting pin 23 or a "⊃" shape assembled through the outer surface of the valve socket 13 It is one of the leaf springs 24 of the bar, and the safety hook 20 is connected to the temporary fixing means, and the fitting pin 23 and the leaf spring 24 are bound for connection of the safety hook 20 A ring 23a and a binding head 24a are provided.

In order for the safety ring 20 to be separated from the valve socket 13 by the temporary fixing means as described above, the C-ring 22 made of a fine wire is stretched and exited from the hook portion 22a, or the fitting pin 23 or Since the plate spring 24 must come out from the corresponding fitting holes 23b, 24b, the deformation load of the C-ring 22 or the fitting pin 23 or the plate spring 24 for the fitting holes 23b, 24b The coupling force (friction force or elastic force) of the air grinder (1) should be less than the load (weight) of the air grinder (1), and in order to ensure the reliable automatic closing (OFF) operation of the safety valve (10), the deformation load or the coupling force is applied to the valve body. (11) The bar should be greater than the frictional force between the valve socket 13, the diameter (thickness) of the C-ring 22, the fitting tolerance of the fitting pin 23, and the material of the plate spring 24 to meet these conditions. The elastic strength and the like are determined.

The reason why the safety hook 20 connected to the valve socket 13 is hung on the wrist of the operator as described above is, while preventing any interference with the grinding work using the air grinder 1, air on the safety hook 20 When the grinder 1 is suspended, the position is to be as far away as possible from the chest or abdomen of the worker, and depending on the situation, the safety hook 20 is placed on other structures adjacent to the work surface, not on the wrist of the worker. It is to be noted that it is possible to hang the safety hook 20 in the form of a tie (straight string) of a predetermined length rather than a ring shape, and a hook or tongs may be connected to the end of the safety hook 20.

In the safety valve 10 according to the second embodiment of the present invention, a lever bracket 25 is assembled and installed on the outer surface of the valve body 11, as shown in FIGS. 8 to 10, and the lever bracket In (25), a link lever 26 selectively protruding from the upper end of the valve rod 12 protruding from the valve body 11 (shutter rod portion in the drawing) is angular motion with the link shaft 25a interposed therebetween. The link shaft 25a is installed so as to penetrate the lower end of the link lever 26 in a horizontal direction at an eccentric position in the direction of one side (left side in the drawing), and the lower end of the link lever 26 The valve rod 12 is formed with an operation cam portion 26a that is inclined in one direction (lower left in the drawing) for the protruding and disengaging operation of the valve rod 12, and the rest of the configuration is the same as in the first embodiment described above.

Therefore, as the link lever 26 is folded in the horizontal direction in the closed (OFF) state of the safety valve 10 shown in FIG. 8, the valve rod 12 is operated by the operating cam portion 26a of the link lever 26. ) Is pushed into the valve body 11, the pneumatic passage of the valve body 11 is opened (ON), as shown in FIG. 10, and the link lever 26 is pulled by the safety ring 20 and thus in the vertical direction. When the valve rod 12 protrudes as it is rebuilt, the pneumatic passage of the valve body 11 is closed, and the open state shown in FIG. 10 can be stably maintained by the elastic force of the coil spring 16, Even if the link lever 26 is further angular movement in the right direction in the drawing beyond the vertical state of FIG. 8, it does not affect the closed state of the safety valve 10.

It is preferable that the operation cam portion 26a is formed to be rounded with a predetermined curvature so that the opening and closing operation of the safety valve 10 as described above can be performed more smoothly and smoothly, and the lever bracket 25 is The hinged angular motion of the link lever 26 based on the link shaft 25a is more stable while being assembled and installed integrally with the valve body 11 by inserting it into the body of the valve body 11 as much as the depth of A bracket with a "∪"-shaped section (refer to FIG. 9) into which the lower part of the link lever 26 is inserted is applied to support the link lever 26, but if it can stably support the hinged angular motion of the link lever 26, the lever It should be noted that there is no restriction on the shape or installation method of the bracket 25 itself, and the safety hook 20 may also be directly hung in the connection hole 26b of the link lever 26, as described above. It can also be connected to the link lever 26 using a water purification end.

The safety valve 10 according to the third embodiment of the present invention is a cap-shaped cover in which the upper portion of the valve rod 12 covers the valve hole 17 as shown in FIGS. 11 to 13. By penetrating the cap 15 and protruding to the outside, the link lever 26 is connected and installed to enable angular movement with the upper end side of the valve rod 12 and the link shaft 25a interposed therebetween. When the valve rod 12 is pulled to the outside by the link shaft 25a as the 26 is bent in the horizontal direction, the pneumatic passage of the valve body 11 is opened (ON), and by the safety ring 20 As the link lever 26 is pulled and re-established in the vertical direction, when the valve rod 12 is pushed back into the inside of the valve body 11 by the link shaft 25a, the pneumatic passage of the valve body 11 is closed. It is made to be (OFF).

As described above, unlike the first and second embodiments, the third embodiment of the present invention opens when the valve rod 12 is pulled to the outside, and closes when the valve rod 12 is pushed into the inside, The opening and closing structure of the pneumatic passage inside the valve body 11 is also slightly different from the first and second embodiments, and the opening and closing structure of the pneumatic passage applied to the third embodiment of the present invention is a valve hole (17). ), and the inlet passage 19b formed just from the bottom of the valve hole 17, and a valve seat 17a provided at a portion where the inlet passage 19b is stepped from the valve hole 17, and the coil spring 16 Is elastically interposed between the valve head 12a and the cover cap 15, the inlet passage 19 communicates with the valve hole 17, and the discharge passage 19a communicates with the inlet passage 19b It becomes the structure that becomes.

As shown more clearly in FIG. 12, the link lever 26 used in the third embodiment of the present invention performs a pulling operation (coil spring compression) of the valve rod 12 centered on the link shaft 25a. It is preferable to form a "∩"-shaped rod receiving part 28 on the lower side into which the upper end of the valve rod 12 is inserted so as to perform more robustly and stably, and the upper surface of the cover cap 15 It is preferable to protrude a pair of protruding jaws 27 in parallel so as to stably support the angular movement of the link lever 26 on both sides, and the rest of the configuration is the same as in the second embodiment described above. It is done.

In addition, the valve rod 12 may protrude in the upper direction of the valve body 11 based on the drawings of the first embodiment described above. The valve rod 12 may protrude in the lower direction of the valve body 11, and in this case, the link lever 26 is also the lower part of the valve body 11 together with the lever bracket 25 or the cover cap 15. It will be disposed on the side, and of course, the inlet passage 19 may be in communication with the rod hole 18 or the inlet passage 19b, and the discharge passage 19a may be in communication with the valve hole 17. .

14 to 17 show the safety valve 10 according to the fourth embodiment of the present invention, and the lever bracket 25 and the link lever 26 applied in the second or third embodiment are attached to a valve body. Safety valve (10) that functions as a gripping handle of the air grinder (1) together with the adjustment knob (7) of the air grinder (1) by placing it on the rear surface (right side in the drawing) not the outer circumferential surface of (11). The lever bracket 25 and the link lever 26 are not protruded on the outer circumferential surface of ), so that the gripping operation of the air grinder 1 is not hindered by the safety valve 10.

To this end, as shown in (A) and (B) of Fig. 16, the valve hole 17 is located at a position corresponding to the upper inner side of the valve body 11 from the rear end of the valve body 11 The inlet passage 19, which is formed to a predetermined depth along the length direction of the pneumatic passage, is a valve hole from the rear end of the valve body 11 to which the hose connector 9 for the pneumatic hose 8 is connected. The discharge passage (19a) extending in parallel with the valve hole (17) from the lower portion of (17) and providing a pneumatic passage is a valve body (11) to which the main body (2) of the air grinder (1) is connected. It is formed through to a position from the front end of the valve hole 17 to the rear inner surface of the valve hole 17, and the valve hole 17 and the inner surface of the inlet passage 19 are connected by an inlet passage 19b in a vertical direction. Installed.

Accordingly, compressed air introduced into the valve body 11 through the pneumatic hose 8 as shown in the direction of the arrow in FIG. 14 passes through the inlet passage 19 and the inlet passage 19b to the inside of the valve hole 17. After the primary inflow, it is supplied to the air grinder 1 through the front end side of the valve body 11 along the discharge passage 19a in communication with the rear side of the valve hole 17, and the flow path of the compressed air A valve mechanism is installed inside the valve hole 17 so that it can be selectively opened and closed, and the inlet passage 19b and the discharge passage 19a are formed on the inlet passage 19 and the valve hole 17, respectively. In order to prevent the leakage of compressed air, a bolt-type seal 30 is installed in the hole through the valve body 11, and the valve hole 17 is inserted into the lower or left side of the valve body 11. Alternatively, the inlet passage 19 may be formed on the right side, and the inlet passage 19 may be formed on the inner upper side or the right side or the left side of the valve body 11.

The valve mechanism (pneumatic passage opening/closing mechanism) applied to the fourth embodiment of the present invention includes a valve rod 12 inserted and installed along the valve hole 17 from the rear end side of the valve body 11, and the valve rod ( The valve head 12a protruding from the front end side (left end in the drawing) of 12), the sealing ring 14 installed on the outer circumferential surface of the valve head 12a, and the sealing ring 14 are selectively in close contact. It is made by including a valve seat (17a) provided along the inner circumferential surface of the valve hole (17) from the rear side of the valve head (12a), and the outer surface of the valve head (12a) including the sealing ring (14) The outer surface of the valve rod 12 is spaced apart from the inner circumferential surface of the valve hole 17 by a predetermined clearance interval (passage interval) over a length range up to a position corresponding to the inlet of the discharge passage 19a.

In addition, the coil spring 16 is elastically interposed between the inner end surface of the valve hole 17 and the valve head 12a, and the coil spring 16 is also stably mounted on the tip surface of the valve head 12a. A spring support part (16a) is provided for, and a cover cap (15) covering the valve hole (17) is assembled and installed in a screw-fastening manner by a fastening part (15b) at the rear end of the valve hole (17). , The rear end of the valve rod 12 penetrates the cover cap 15 and protrudes to the outside of the valve body 11 by a predetermined length, and the opening and closing operation of the pneumatic passage is performed using the elastic force of the coil spring 16. The link lever 26 for performing is connected to enable angular movement with the link shaft 25a interposed on the lever bracket 25 installed integrally with the cover cap 15 at the rear surface of the cover cap 15 Installed.

In other words, the valve mechanism applied to the fourth embodiment of the present invention may be interpreted as having the valve mechanism of the second embodiment described above laid down in a horizontal direction, and if necessary, the valve of the third embodiment described above. It should be noted that it is possible to apply the mechanism to the fourth embodiment, and in this case, the link lever 26 passes through the cover cap 15 and extends to the outside as shown in Figs. It will be connected to the lever bracket 25 by the link shaft 25a with the rear end of 12, and the coil spring 16 is also elastically interposed between the valve head 12a and the valve seat 17a. In the first and second embodiments, a sealing ring 14 may be installed at the rear outer periphery of the valve rod 12 penetrating the cover cap 15 to prevent leakage of compressed air. It is preferable to apply the same taper hole 18a and shutter rod 12c.

Even more preferably, the valve seat 17a is formed on the front end side (left end in the drawing) of the cover cap 15 so that the valve seat 17a is formed in the valve hole 17 when the valve hole 17 is processed. The bar is to eliminate the tricky work to form on the inner circumferential surface, for this purpose, the cover cap 15 is inserted and installed in a pipe shape by a predetermined depth through the valve hole 17, and the rear side of the valve seat 17a A communication hole 29 for communicating the inlet passage 19b on the front end side of the inlet passage 19 with the discharge passage 19a on the rear side of the valve hole 17 is formed in the body portion of the cover cap 15 corresponding to The inner circumferential surface of the cover cap 15 provided with the communication hole 29 and the outer surface of the valve rod 12 are spaced apart by a predetermined distance, while the cover cap 15 provided with the communication hole 29 is A predetermined clearance gap is provided between the outer circumferential surface and the inner circumferential surface of the valve hole 17 to a position reaching the inlet of the discharge passage 19a.

In the case of the safety valve 10 according to the fourth embodiment of the present invention, the link lever 26 is angularly moved to the front side (left side in the drawing) as in Fig. 17(A) as well. When the valve rod 12 is pushed into the valve body 11 by the operating cam portion 26a of the link lever 26 according to the bending, the pneumatic passage of the valve body 11 is opened (ON), and FIG. 17 As in (B) of, when the link lever 26 is pulled to the rear side (right side in the drawing) by the safety ring 20 and the valve rod 12 protrudes, the pneumatic passage of the valve body 11 It is closed (OFF), and the open state shown in (a) of FIG. 17 can be stably maintained by the elastic force of the locking protrusion 26c and the coil spring 16 provided on the link lever 26.

In the second and third embodiments described above, the operating cam portion 26a of the link lever 26 is formed with an inclined surface that is inclined to be round in one direction, and the link lever 26 according to the fourth embodiment The operating cam portion (26a) of is shown to have a square plate shape rounded in a chamfered only the corner portion, but the link shaft (25a) is passed through the eccentric position of the link lever (26) of the valve rod (12). The shape of the operating cam unit 26a itself is not limited as long as it is possible to perform a cam-driven operation, and various types of operation cam units 26a other than those shown in the drawings may be applied. To reveal.

According to the present invention having the configuration as described above, when the valve socket 13 is pushed forward or the link lever 26 is tilted in the horizontal direction, the pneumatic passage of the valve body 11 is opened (ON). Grinding by the grinder (1) is possible, and if the air grinder (1) is dropped due to an operator's mistake or carelessness, the air grinder (1) is placed on the safety hook (20) hung on the wrist of the operator. As soon as the hanging situation occurs, the valve socket 13 slides to the rear side of the valve body 11 (the front body of the valve body comes out of the valve socket by the load of the air grinder) or the link lever 26 moves in the vertical direction. As the pneumatic path is retracted again, the pneumatic path can be automatically set to a closed (OFF) state, and various safety accidents such as cutouts or cutting accidents that occur when the air grinder 1 is used can be prevented in advance.

In addition, an airtight means that prevents compressed air from leaking into a portion where the end side of the valve rod 12 passes through the body of the valve body 11 without causing any hindrance to the protruding operation at the end side of the valve rod 12. By providing, it is possible to ensure the normal operation of the air grinder 1 by zeroing the loss of pneumatic pressure flowing from the pneumatic hose 8 through the valve body 11 to the air grinder 1, and in particular, a shutter having a trapezoidal cross section. When the rod 12c and the tapered hole 18a are applied as airtight means, an economical and reasonable sealing structure capable of blocking the leakage of compressed air can be provided even if consumables requiring frequent replacement such as sealing rings are not used. have.

In addition, while forming the inner peripheral surface of the front end of the valve socket 13 with a tapered portion 13a inclined in the inward direction, the end side of the valve rod 12, that is, the shutter rod 12c and the shutter cap 12d As the end surface of the valve body 11 is formed to be rounded in a spherical shape, the end side of the valve rod 12 protruding from the valve body 11 can be quickly and accurately pushed into the body of the valve body 11. By installing a cover cap (15) that can selectively open the hole (17), repair or replacement of the valve rod (12) and coil spring (16) including the sealing ring (14) and valve hole (17) Maintenance work for the interior of the car can be performed more quickly and easily.

As an additional matter, immediately after the pneumatic passage is completely closed as the air grinder (1) is suspended from the safety hook (20) on the wrist of the operator, the entire load of the air grinder (1) is concentrated on the safety hook (20). By applying a temporary fixing means that automatically separates the safety ring 20 from the valve socket 13 or the link lever 26 at the point of time, it rotates by the residual centrifugal force even after the pneumatic passage is closed by the valve rod 12. The situation in which the grinder wheel 4 is in contact with the body of the worker can be fundamentally blocked, and through this, various safety accidents that may occur when the air grinder 1 is used can be more reliably prevented.

On the other hand, as in the case of the fourth embodiment, when the lever bracket 25 and the link lever 26 constituting the safety valve 10 are disposed on the rear surface of the valve body 11 rather than the outer circumferential surface, air A lever bracket (25) and a link lever (26) are located on the outer circumferential surface of the safety valve (10), which functions as a gripping handle of the air grinder (1) together with the adjustment knob (7) of the grinder (1). As it can be prevented from protruding, the gripping operation of the air grinder 1 can be prevented from being disturbed by the safety valve 10, and through this, the safety and workability of the air grinder 1 can be secured at the same time. will be.

1: air grinder 2: main body 3: gearbox
4: grinder wheel 5: safety cover 6: handle
7: adjustment knob 8: pneumatic hose 9: hose connector
10: safety valve 11: valve body 11a: front body
11b: rear body 11c, 15b: fastening part 11d: shutter storage groove
12: valve rod 12a: valve head 12b: connecting rod
12c: shutter rod 12d: shutter cap 13: valve socket
13a: tapered portion 13b: protruding jaws 13c, 18b: through hole
14: sealing ring 15: cover cap 15a: tool groove
15c: cap hole 16: coil spring 16a: spring support
17: valve hole 17a: valve seat 18: rod hole
18a: tapered hole 19: inlet passage 19a: discharge passage
19b: entrance passage 20: safety hook 20a: fitting bolt
20b: fastening hole 21: stopper 21a: mounting groove
22: C ring 22a: hook portion 23: fitting pin
23a: binding ring 23b, 24b: fitting hole 24: leaf spring
24a: binding head 25: lever bracket 25a: link shaft
26: link lever 26a: operating cam portion 26b: connection hole
26c: locking jaw 27: protruding jaw 28: rod receiving portion
29: communication hole 30: sealing port

Claims (12)

A pipe type valve body that provides a pneumatic passage from the pneumatic hose (8) to the air grinder (1) by connecting the main body (2) of the air grinder (1) to the front end and the pneumatic hose (8) to the rear end. (11), a valve hole (17) formed to be connected with a pneumatic passage from the inside of the valve body (11), and a predetermined outside the body of the valve body (11) while being inserted into the inside of the valve hole (17). A valve rod 12 protruding as long as the length of, and an opening/closing mechanism of a pneumatic passage that is installed outside the valve body 11 to selectively protrude a portion of the valve rod 12 protruding from the valve body 11, and the A coil spring (16) installed inside the valve hole (17) to elastically support the protruding operation of the valve rod (12), and the valve rod (12) is protruding and protruding from the inside of the valve body (11). In the safety valve 10 for an air grinder 1 provided with an opening and closing structure for opening and closing a pneumatic passage according to operation,
The opening/closing mechanism of the pneumatic passage is a cylindrical valve socket (13) that slides forward and backward along the outer surface of the valve body (11) and selectively protrudes from the valve rod (12) portion protruding from the valve body (11). In addition, a tapered portion 13a for pushing the valve rod 12 protruding out of the valve body 11 into the inside of the valve body 11 is provided on the inner side of the front end of the valve socket 13, and , On the outer surface of the valve socket 13, a safety hook 20 for hanging on the operator's wrist is connected and installed,
The opening operation of the pneumatic passage is performed in such a way that the operator moves the valve socket 13 to the front side and pushes the part of the valve rod 12 protruding from the valve body 11 into the inside of the valve body 11, and the In the closing operation of the pneumatic passage, as soon as the operator accidentally or carelessly drops the air grinder (1), the air grinder (1) hangs from the safety hook (20) hung on the operator's wrist. A safety valve for an air grinder, characterized in that the valve socket 13 connected to the) automatically slides to the rear side so that the valve rod 12 protrudes from the valve body 11. The main body (2) of the air grinder (1) is connected to the front end and the pneumatic hose (8) is connected to the rear end to provide a pneumatic passage from the pneumatic hose (8) to the air grinder (1). ), and a valve hole 17 formed to be connected with a pneumatic passage in the inside of the valve body 11, and a predetermined length outside the body of the valve body 11 while being inserted into the inside of the valve hole 17 The valve rod 12 protruding by the same amount, the opening and closing mechanism of the pneumatic passage for selectively protruding the valve rod 12 portion protruding from the valve body 11 by being installed outside the valve body 11, and the valve hole (17) is installed in the inside of the coil spring (16) to elastically support the protruding operation of the valve rod (12), and the inside of the valve body (11) to the protruding operation of the valve rod (12) Accordingly, in the safety valve 10 for the air grinder 1 provided with an opening and closing structure for opening and closing the pneumatic passage,
The opening/closing mechanism of the pneumatic passage is connected and installed to enable angular movement with a lever bracket 25 assembled and installed on the outer surface of the valve body 11 and a link shaft 25a interposed on the lever bracket 25 And a link lever 26 for selectively protruding and protruding from the valve body 11, and the link shaft 25a is a link lever 26 at an eccentric position in one direction. It is installed to penetrate the end side of the horizontal direction, and the end surface of the link lever 26 through which the link shaft 25a passes is formed as an operating cam part 26a for the protruding operation of the valve rod 12, and the At the other end of the link lever 26, a safety hook 20 for hanging on the wrist of the operator is connected and installed,
The opening operation of the pneumatic passage is performed by the operator bending the link lever 26 in the horizontal direction, and the valve rod 12 part protruding from the valve body 11 is moved to the inside of the valve body 11 by the operating cam part 26a. The air grinder 1 hangs on the safety hook 20 hung on the wrist of the operator as the operator accidentally or carelessly drops the air grinder 1 in the closing operation of the pneumatic path. As soon as the situation arises, the link lever 26 connected to the safety hook 20 is pulled in a vertical direction and re-established, and a method of causing the valve rod 12 to protrude to the outside of the valve body 11 is included. Safety valve for air grinder. The main body (2) of the air grinder (1) is connected to the front end and the pneumatic hose (8) is connected to the rear end to provide a pneumatic passage from the pneumatic hose (8) to the air grinder (1). ), and a valve hole 17 formed to be connected with a pneumatic passage in the inside of the valve body 11, and a predetermined length outside the body of the valve body 11 while being inserted into the inside of the valve hole 17 The valve rod 12 protruding by the same amount, the opening and closing mechanism of the pneumatic passage for selectively protruding the valve rod 12 portion protruding from the valve body 11 by being installed outside the valve body 11, and the valve hole (17) is installed in the inside of the coil spring (16) to elastically support the protruding operation of the valve rod (12), and the inside of the valve body (11) to the protruding operation of the valve rod (12) Accordingly, an opening/closing structure for opening and closing the pneumatic passage is provided, and a cover cap 15 in the shape of a stopper covering the valve hole 17 is assembled and installed on the body side of the valve body 11, and the valve rod 12 is a cover It passes through the cap 15 and protrudes to the outside of the valve body 11 by a predetermined length, and the coil spring 16 is between the valve head 12a at the front end of the valve rod 12 and the cover cap 15 In the safety valve 10 for the air grinder (1) elastically interposed in the,
The opening/closing mechanism of the pneumatic passage is installed to enable angular movement with the rear end side of the valve rod 12 protruding to the outside of the cover cap 15 and the link shaft 25a interposed therebetween. It becomes a link lever 26 performing a protruding operation, and the link shaft 25a is installed to penetrate the rear end side of the link lever 26 in a horizontal direction at an eccentric position in one direction, and the link shaft 25a The end surface of the link lever 26 through which) is penetrated is formed with an operating cam part 26a for the protruding and disengaging operation of the valve rod 12, and the other end of the link lever 26 is for hanging on the wrist of the operator. Safety hook (20) is connected and installed,
The opening operation of the pneumatic passage is performed in such a manner that the valve rod 12 is pulled out of the valve body 11 by the link shaft 25a as the operator tilts the link lever 26 in the horizontal direction, In the closing operation of the pneumatic path, as the operator accidentally or carelessly drops the air grinder 1, as soon as the air grinder 1 is suspended from the safety hook 20 hung on the operator's wrist, the safety hook ( Air, characterized in that it includes a method of pushing the valve rod 12 into the inside of the valve body 11 by the link shaft 25a while the link lever 26 connected to the 20) is pulled in a vertical direction and rebuilt. Safety valve for grinder. The method according to claim 1 or 2, wherein the opening and closing structure of the pneumatic passage is formed stepped from the lower side or the upper side of the valve hole 17 to the inner side, while the outer surface of the valve rod 12 and a predetermined clearance interval are provided. It is provided on the basis of a rod hole 18 spaced apart and a through hole 18b formed to be stepped inward from the lower or upper side of the rod hole 18 to contact the outer surface of the valve rod 12,
In the pneumatic passage, the inlet passage 19 extends from the rear end of the valve body 11 to which the pneumatic hose 8 is connected, so that the outlet of the inlet passage 19 communicates with the valve hole 17, and the air grinder The discharge passage (19a) is extended from the front end of the valve body (11) to which the main body (2) of (1) is connected, so that the inlet of the discharge passage (19a) communicates with the rod hole (18). ,
As a means for opening and closing the pneumatic passage, a valve head 12a that is elastically supported by a coil spring 16 is protruded at one end of the valve rod 12, and the outer circumferential surface of the valve head 12a and the valve hole 17 A predetermined clearance is provided between the inner circumferential surfaces of the valve, and the stepped portion between the valve hole 17 and the rod hole 18 provides a valve seat 17a for seating the valve head 12a, and the valve head Safety valve for an air grinder, characterized in that the sealing ring 14 in close contact with the valve seat (17a) is installed on the outer circumferential surface of (12a). The method according to claim 2, wherein the valve hole (17) is formed along the longitudinal direction of the valve body (11) from the rear end of the valve body (11) at a position corresponding to the inner upper portion or the inner lower portion of the valve body (11). , The pneumatic passage is an inlet passage 19 extending in parallel with the valve hole 17 from the lower or upper portion of the valve hole 17 from the rear end of the valve body 11 to which the pneumatic hose 8 is connected, The inlet passage 19b communicating the inner end of the inflow passage 19 with the inner end of the valve hole 17, and the valve body 11 to which the main body 2 of the air grinder 1 is connected. It is made by including a discharge passage (19a) formed through from the front end to the position reaching the rear inner surface of the valve hole (17),
The opening and closing structure of the pneumatic passage includes a valve rod 12 inserted and installed along the valve hole 17 from the rear end side of the valve body 11, and a valve head protruding from the front end side of the valve rod 12 ( 12a), the sealing ring 14 installed on the outer circumferential surface of the valve head 12a, and the inner circumferential surface of the valve hole 17 at the rear side of the valve head 12a so that the sealing ring 14 is selectively contacted. The outer surface of the valve head 12a including the sealing ring 14 and the outer surface of the valve rod 12 are formed by including the valve seat 17a provided along with the inner circumferential surface of the valve hole 17 It is made to be spaced apart at intervals of,
The coil spring 16 is elastically interposed between the front inner surface of the valve hole 17 and the valve head 12a, and a cover cap covering the valve hole 17 at the rear end of the valve hole 17 15 is assembled and installed, and the rear end of the valve rod 12 penetrates the cover cap 15 and protrudes to the outside of the valve body 11 by a predetermined length, and the lever bracket 25 is a link lever ( A safety valve for an air grinder, characterized in that it is connected to the rear end of the cover cap (15) with 26) interposed therebetween. The method of claim 5, wherein the cover cap (15) is inserted and installed in a pipe shape by a predetermined depth through the valve hole (17), and the valve seat (17a) is provided on the front end side of the cover cap (15), In the body portion of the cover cap 15 corresponding to the rear side of the valve seat 17a, the inlet passage 19b on the front end of the inlet passage 19 communicates with the discharge passage 19a on the rear side of the valve hole 17. A communication hole 29 is formed to allow the communication hole 29 to be provided, and the inner side portion of the cover cap 15 provided with the communication hole 29 and the outer side portion of the valve rod 12 are spaced apart at a predetermined interval, while the cover A safety valve for an air grinder, characterized in that a sealing ring (14) is installed at the rear outer periphery of the valve rod (12) passing through the cap (15). The method of claim 3, wherein the opening and closing structure of the pneumatic passage comprises an inlet passage (19b) formed to be stepped from a lower side or an upper side of the valve hole (17) and an inlet passage (19b) from the valve hole (17). It comprises a valve seat 17a provided on the losing part, and a sealing ring 14 installed on the outer circumferential surface of the valve head 12a of the valve rod 12 and in close contact with the valve seat 17a,
In the pneumatic passage, the inlet passage 19 extends from the rear end of the valve body 11 to which the pneumatic hose 8 is connected, so that the outlet of the inlet passage 19 communicates with the valve hole 17, and the air grinder The discharge passage 19a is extended from the front end side of the valve body 11 to which the main body 2 of (1) is connected, so that the inlet of the discharge passage 19a communicates with the inlet passage 19b. Safety valve for air grinder characterized by. According to claim 4, Between the through hole (18b) of the valve body (11) and the valve rod (12) an airtight structure for blocking leakage of pneumatic pressure is additionally provided, the airtight structure is the valve rod (12) The end side of is formed with a shutter rod 12c having a trapezoidal cross section, while the through hole 18b is a structure formed by a taper hole 18a having a trapezoidal cross section that is in close contact with the outer surface of the shutter rod 12c in a wedge manner. Or a shutter cap (12d) protruding from the end of the valve rod (12), and a sealing ring (14) covering the lower circumference of the through hole (18b) on the upper side of the shutter cap (12d). Safety valve for an air grinder, characterized in that the structure is mounted. The method of claim 8, wherein the shutter rod (12c) and the shutter cap (12d) are assembled and installed detachably from the valve rod (12), and the valve body (11) performs a cover function of the valve hole (17). The cover cap 15 is assembled and installed,
Ends of the shutter rod 12c and the shutter cap 12d are formed to be rounded in a spherical surface, and the shutter cap 12d is inserted into the outer surface of the valve body 11 in close contact with the shutter cap 12d. The shutter housing groove (11d) is formed concave,
The valve body 11 is assembled with a cover cap 15 in the shape of a stopper that performs a stopper function of the valve hole 17, and the coil spring 16 is formed between the valve head 12a and the cover cap 15. Are elastically interposed between them,
The cover cap 15 is fastened and installed with the sealing ring 14 interposed along the cap hole 15c formed to penetrate the body portion of the valve body 11 in the direct upper or lower part of the valve hole 17. Safety valve for an air grinder, characterized in that. According to claim 1, wherein the valve body (11) is a rear body (11b) to which the pneumatic hose (8) is connected from the front body (11a) part connected to the main body (2) of the air grinder (1) is inside And the valve rod 12 is installed on the front body 11a of the valve body 11 together with the valve hole 17,
On the inside of the rear end of the valve socket 13, a protruding jaw 13b is formed between the front body 11a and the rear body 11b, while the tapered portion 13a is A safety valve for an air grinder, characterized in that it is formed over the inner peripheral surface of the front end side, and is provided with a stopper (21) means for preventing separation of the valve socket (13) on the rear end side of the rear body (11b). According to any one of claims 1 to 3, wherein the safety ring (20) is connected to the valve socket (13) or the link lever (26), the air grinder (1) is suspended from the safety ring (20). When the entire load of the air grinder 1 acts on the safety ring 20, a temporary fixing means for automatically separating the safety ring 20 from the valve socket 13 or link lever 26 is applied. Safety valve for air grinder. 12. The method of claim 11, wherein the temporary fixing means is other than a wire material C-ring (22) or valve socket (13) or link lever (26) connected on the outer surface of the valve socket (13) or link lever (26). Safety for an air grinder, characterized in that it is selected from the fitting pin 23 or the "⊃"-shaped leaf spring 24 that is assembled through the side, and the safety ring 20 is connected to the temporary fixing means. valve.

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