JPS5935634Y2 - hydraulic chuck - Google Patents

Description

[Detailed Description of the Invention] This invention mainly relates to a hydraulic chuck for gripping an injection pipe or the like for injecting a hardening agent, a stabilizer, etc. into soft ground and applying rotational force and propulsive force to the chuck.

In a conventional hydraulic chuck of this type, a chuck jaw is attached to the tip of a chuck base connected to a rotating and propulsion spindle, and the base of this chuck jaw is brought into contact with one end of a link lever provided on the outer periphery of the chuck jaw holder. It is known that a roller provided at the other end of the link lever is pushed up by a taper block provided on a hydraulically actuated piston to propel the chuck jaw via the link lever.
No. 1).

However, in such conventional hydraulic chucks, since the chuck jaw has a rectangular cross section, it is not possible to seal the four circumferences where it slides on the chuck holder with an O-ring, etc. Therefore, for example, a soil hardening agent injection pipe cannot be connected to the chuck base. When the injection tube is pulled up through the spindle, the curing agent and the like adhering to the outer periphery of the injection tube enters the interior through the gap around the chuck jaws, solidifying the chuck jaws and rendering them inoperable.

In addition, the mechanism for moving the chuck jaw back and forth requires non-rotating hydraulic chambers before and after moving the piston back and forth, a taper block rotatable through a bearing with respect to the piston, a link lever, and a ring spring for moving the chuck jaw back.
It was structurally extremely complex, difficult to assemble, and had many manufacturing and cost issues, including a large number of parts.

In order to solve the above-mentioned conventional problems, this invention proposes a hydraulic chuck with a simple and compact structure that seals around the chuck jaws to reliably prevent entry of hardening agent and the like.

An example of this invention shown in the drawings will be explained below.
The hydraulic chuck body 1 includes a cylindrical spindle connecting member 2, a chuck holder 3 whose tip is fitted into the tip of the spindle connecting member, and a chuck holder 3 provided on the outer periphery of each rear end of the spindle connecting member 2 and the chuck holder 3. Outer flange 2
It is integrally constructed with a sleeve 5 which is connected and fixed with a bolt 4 between ' and 3'.

On the inner periphery of the rear end of the spindle connecting member 2, there is a pressure oil introducing groove 6 in the circumferential direction, and an annular hydraulic chamber formed between the spindle connecting member 2 and the sleeve 5, passing from a part of this groove into the outer peripheral flange 2'. A pressure oil passage 8 communicating with 7 is formed.

A spindle 9 of a rotation and propulsion device is fitted into the rear end of this spindle connecting member 2, and its end is connected to an inner peripheral flange 10 provided on the inner peripheral part of the spindle connecting member 2.
are connected and fixed with bolts 11.

The spindle 9 has a pressure oil flow path 12 that passes from the outer periphery of the non-fitting portion through the inside and communicates with the pressure oil introduction groove 6 of the spindle connecting member 2.
A non-rotating oil supply member 14 having a pressure oil supply groove 13 on the inner circumference is slidably attached to the outer periphery of the inlet portion thereof.

A hydraulic pipe 15 that introduces pressure oil into the oil supply groove 13 is connected to the oil supply member 14 .

A cylindrical piston 16 is mounted in an annular space between the spindle connecting member 2, the chuck holder 3, and the sleeve so as to be slidable back and forth, and its rear end is inserted into the hydraulic chamber 7.

Tapered grooves 17 having a T-shaped vertical section are formed at multiple locations on the inner periphery of the tip of the piston 16 and are inclined from the inner periphery of the piston toward the outer periphery of the piston toward the forward direction. A plurality of rollers 18 are placed at predetermined intervals.
is rotatably supported.

In a portion of the chuck holder 3 facing the tapered groove 17, a plurality of sliding holes 20 having a circular cross section are provided in the radial direction, into which chuck jaws 19 having a circular cross section are slidably fitted.

The chuck jaw 19 is fitted with an O-ring 21 around it to form an airtight seal between the chuck jaw 19 and the circular sliding hole 20.
The tip is formed in a V shape, and a cemented carbide biting blade 22 is attached to the surface of the tip.
is fixed thereto, and a tapered rail 23 that is slidably fitted into the tapered groove 17 and has a T-shaped longitudinal section and is inclined like the tapered groove 17 is provided at the rear end.

Spring fitting holes 24 and 25 are provided in multiple locations at the tip of the piston 16 and in the outer peripheral flange 3' of the chuck holder 3 facing thereto, and a return spring 26 is installed between the bottom surfaces of the holes 24 and 25. There is.

Note that 27, 28, 29, 30, 31, and 32 in the figure are O-rings that seal with each part.

In the above-mentioned seizure, 33 pieces of injection pipes, drilling pipes, etc.
When inserting or pulling up underground while rotating (in this case, hydraulic pipe 15, upper pond supply groove 1
3. Pressure oil is fed to the hydraulic chamber 7 through the pressure oil passage 12, the pressure oil introduction groove 6, and the pressure oil passage 8, and the piston 16 is moved forward.

When the piston 16 moves forward, the rollers 18 are formed in the tapered groove 17.
The chuck jaw 19 moves forward in the axial direction of the chuck holder via the tapered rail 23 which is fitted in contact with the chuck holder, and chucks the tube body 33 inserted thereinto.

In this state, the spindle 9 is rotated to rotate the tube body 33,
Further, the spindle 9 is moved back and forth to move the tube body 33 back and forth.

When releasing the chuck, the piston 16 returns to the spring 26 by stopping the pressure oil supply and releasing the hydraulic pressure.
is pushed back by the elasticity of the chuck jaw 1.
Pull back 9 and move back.

As mentioned above, according to this invention, the chuck jaw has a circular cross section and its circumference is sealed with an O-ring.
There is no intrusion of hardening agent or the like from around the chuck jaws, and therefore it is possible to eliminate failures such as inoperability due to intrusion and solidification of hardening agent as in the prior art.

In addition, the chuck jaw moves forward with a T-shaped taper rail provided at its rear end using hydraulic pressure, and fits into a T-shaped tapered groove provided in a piston that is moved backward by a return spring, so that it moves forward and backward as the piston advances and retreats. Unlike conventional systems, there is no need for link levers, etc., and a single hydraulic supply path allows pressure oil to be supplied from the outside of the spindle, reducing the overall number of parts and making the structure more compact. It is also easy to manufacture and can reduce manufacturing costs.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of this invention, and FIG. 2 is a cross-sectional view taken along line AA in FIG. 3...Chuck jaw holder, 19...
...Chuck jaw, 21...O ring, 16
... Piston, 17... Taper groove,
23... Taper rail, 26... Return spring.

Claims (2)

[Scope of utility model registration request] (1) A cylindrical chuck holder is provided with a plurality of sliding holes each having a circular cross section in the radial direction, a chuck jaw having a circular cross section is slidably fitted into each of the sliding holes, and the sliding hole A hydraulic chuck characterized by having the sliding surfaces of the chuck jaws sealed with an O-ring. (2) The outer circumference of the chuck holder moves forward using hydraulic pressure.
A cylindrical piston that is retracted by a return spring is provided, and the inner circumferential surface of the piston facing the chuck jaw is provided with a T-shaped taper in longitudinal section that is inclined from the inner circumferential side to the outer circumferential side in the forward movement direction of the piston. A groove is provided, and a tapered rail that is slidably fitted in the tapered groove and has a T-shaped longitudinal section and is inclined in the same manner as the tapered groove is provided in the short rear portion of the chuck jaw that faces the tapered groove of the piston. A hydraulic chuck according to claim 1 of the utility model registration claim, characterized in that: