JP2918128B2 - jack - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a jack used for a wheel inspection of a landing gear wheel holding an aircraft wheel, for example.

[0002]

2. Description of the Related Art As a jack used for a wheel inspection of a landing gear wheel holding an aircraft wheel, there is a jack having a structure as shown in FIG.

That is, the jack has a concave spherical surface 2a on an upper end surface of a ram 2 protruding upward from an upper end of a jack body 1 installed on the ground surface G. Has a landing gear wheel (not shown)
A jack point P protruding downward at the lower end of the seat is seated.

Therefore, when the jack is used, the concave spherical surface 2 is used.
If jack point P is seated correctly on a,
The load applied via the jack point P acts on the axis of the ram 2, so that the jack body 1, that is, the jack is stabilized on the ground surface G, and normal operation thereof can be expected.

[0005]

However, the use of the jack having the structure shown in FIG. 3 may be inconvenient.

That is, in consideration of the actual situation when using this type of jack, it is not easy to position the concave spherical surface 2a directly below the jack point P, and therefore, in fact, the jack main body 1 is almost completely relied on by feeling. It is installed on the surface G, and the jack body 1 is operated from this state to raise the ram 2.

As a result, as shown in FIG. 3, the jack point P may be seated on the concave spherical surface 2a in a so-called eccentric state with respect to the concave spherical surface 2a, and the ram 2 is further raised from this state. As shown in FIG. 4, the jack is set on the ground surface G with a slight inclination at the angle θ.

At this time, a large load W acting on the jack from the landing gear wheel via the jack point P is supported by a fulcrum C which is a contact point between a part of the lower edge of the jack body 1 and the ground surface G. become.

As a result, when the landing gear wheel is rotated in this state for the inspection as shown by the arrow in the figure, the jack is turned in the same direction as the rotation direction of the landing gear wheel, and extremely. Of course, there is a danger that the operation of the operation rod 3 or the foot pedal 4 in the jack may become impossible depending on the turning state of the jack.

The present invention has been made in view of the above circumstances, and has as its object to stably operate even if it is not possible to position the concave spherical surface directly below the jack point during use. An object of the present invention is to provide a jack capable of supporting a large load from above in a state.

[0011]

In order to achieve the above object, the present invention provides a jack body, a ram protruding upward and downward from the jack body, and a horizontal movably mounted on an upper end of the ram. The ram has a concavely arranged spherical surface formed on the upper end face of the metallic shell for seating an upper jack point, and the ram has a space portion that opens upward, and is formed in the space portion. Is inserted in the center of the lower end of the receiving metal so as to be movable downward in the horizontal direction, and the shaft center of the receiving metal is inserted between the shaft and the bottom of the space. The present invention is characterized in that a return spring for urging the receiver in the same direction is interposed.

Preferably, the lower end of the receiving member is connected to the upper end of a return spring fixed to the ram.

[0013]

[Function] Therefore, the jack body is installed on the ground surface with consideration given so that the concave spherical surface is positioned almost directly below the jack point, and when the jack body is operated from this state to raise the ram, the jack point becomes concave. Even in the case of sitting in a so-called eccentric state with respect to the spherical surface, the receiver having the concave spherical surface moves in the horizontal direction within its allowable range,
The jack point will be seated accurately against the concave spherical surface.

As a result, the jack body is in a stable state,
That is, the jack is installed without being inclined with respect to the ground surface, and a large load acting on the jack from the landing gear wheel via the jack point is applied to the wide contact surface between the lower end surface of the jack body and the ground surface. Will be supported.

Therefore, even if the landing gear wheel is rotated for the inspection in this state, the jack is not rotated, and the operation of the operating rod or the foot pedal in the jack becomes impossible. Things won't come.

When the return spring is interposed, the receiver can always return to the axial center position with respect to the ram when the effect of the eccentric load on the receiver is released. That is, the transfer of the receipt at the next opportunity is maintained in a possible state.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, a jack according to an embodiment of the present invention is basically constructed in the same manner as the conventional example described above, and is installed on the ground surface G. And a ram 2 protruding upward from an upper end of the jack body 1.

In the present invention, the ram 2
At the upper end thereof has a metal receiving member 5 arranged movably in the horizontal direction, and has a concave spherical surface 5a on the upper end surface of the metal receiving member 5, and a landing gear wheel (see FIG. (Not shown), a jack point P projecting downward is seated.

The jack body 1 is provided with an operation rod 3 for raising the ram 2 during the swinging operation and a foot pedal 4 for lowering the ram 2 in the raised state when the stepping operation is performed.

By the way, it is assumed that the receiving money 5 is disposed at the upper end of the ram 2 so as to be movable in the horizontal direction. The structure is as follows.

That is, as shown in FIG. 2, the ram 2 is formed in a substantially funnel shape on the shaft core on the upper end side thereof, and has a space 2b which is open on the upper end surface. Has an annular seat portion 2c.

On the other hand, the receiving metal 5 has a concave spherical surface 5 on its upper end surface.
a, but of course, has a shaft portion 5b protruding downward at the center of the lower end surface thereof, that is, so as to be present in the space portion 2b. A shoulder 5c is formed annularly on the lower end surface on the side and is slidably contacted with the seat 2c.

The shaft 5b is set so as to have an appropriate gap between the outer periphery and the inner periphery of the space 2b when the shaft 5b is present in the space 2b. .

Therefore, the receiving member 5 is in a range in which the shaft portion 5b can move in the space 2b, that is, in a range of the stroke S with respect to the shaft center position of the ram 2 as shown in the drawing. It is possible to move in the horizontal direction which is the left and right in the figure.

At this time, the shoulder 5c of the receiving money 5 is
Of course slides on the seat 2.

The jack according to the present invention is constructed as described above. In this embodiment, the following consideration is further taken.

That is, as shown in FIG. 2, the receiver 5 is connected to an upper end of a return spring 6 fixed to the ram 2.

Explaining a little, the return spring 6 is
The lower end is locked by a spring holder 7 housed in the inner bottom of the space 2b, and the upper end is locked by a headed pin 8 planted on the lower bottom surface of the shaft 5b. The receiving metal 5 is positioned at the center of the upper end of the ram 2 by the restoring force, that is, the axis of the receiving metal 5 is aligned with the axis of the ram 2.

The spring holder 7 is engaged with a pin 9 which is press-fitted into a through hole 2d formed in the body of the ram 2 in a radial direction. The escape from the bottom is prevented.

In the jack according to this embodiment formed as described above, at the time of its use, the jack body 1 is arranged so that the concave spherical surface 5a of the receiving metal 5 is positioned substantially immediately below the jack point P. Is set on the ground surface G, and the jack body 1 is operated from this state to raise the ram 2, so that the jack point P becomes the concave spherical surface 5a.
Even if it becomes a situation of sitting in a so-called eccentric state,
The receiver 5 having the concave spherical surface 5a moves in the horizontal direction within the allowable range, and the jack point P is accurately seated on the concave spherical surface 5a.

At this time, the jack body 1 is stably installed on the ground surface G, and a large load W acting on the jack from the landing gear wheel via the jack point P (see FIG. 4). Is supported by a wide contact surface between the lower end surface of the jack body 1 and the ground surface G.

In this state, even if the landing gear wheel is rotated for the inspection, the jack is not rotated, and the operation of the operation rod 3 and the foot pedal 4 in the jack becomes impossible. Disappears.

[0033]

As described above, according to the present invention, even when the jack body is not always accurately set at a so-called fixed position at the time of its use, the jack point from the landing gear wheel is connected to the upper end of the ram. There is an advantage that the seat can be accurately seated on the concave spherical surface of the above, and a large load acting on the jack can be supported in a stable state.

Further, according to the present invention, the structure is simple because there is only one receiving metal, and the axis of the receiving metal coincides with the axis of the ram between the shaft and the bottom of the space. Since the return spring that urges the receiver is interposed, the receiver can automatically return to the axial center position with respect to the ram when the effect of the eccentric load on the receiver is released. This has the advantage of keeping the receipt of money at the next opportunity possible.

[Brief description of the drawings]

FIG. 1 is a front view showing a jack according to an embodiment of the present invention in a partially broken state.

FIG. 2 is a partially enlarged front view showing a main part of the jack shown in FIG.

FIG. 3 is a front view showing a conventional jack as in FIG.

FIG. 4 is a front view showing an operation state of the conventional jack shown in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Jack main body 2 Ram 3 Operation handle 4 Foot pedal 5 Receipt 5a Concave spherical surface 6 Return spring G Ground surface P Jack point

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B66F 3/38 B66F 3/36

Claims (1)

(57) [Claims] 1. A jack body, a ram protruding upward and downward from the jack body so as to be able to move up and down, a metal receiver disposed at an upper end of the ram so as to be movable in a horizontal direction, and formed on an upper end surface of the metal receiver. The ram has a concave spherical surface on which the upper jack point is seated, and a space is formed in the ram so as to open upward. And a return spring that urges the shaft in the direction that matches the shaft of the ram with the shaft of the ram is interposed between the shaft and the bottom of the space. Jack.