JPH0235200B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a tripod for photography, movies, and television photography;
This invention relates to a telescopic leg body used for monopods and the like.

[Conventional technology]

This type of telescopic leg tube, which is convenient to carry and store, is generally made by inserting several leg tubes with slightly different diameters into a larger tube one after another, with the smaller tube diameter inside. The extended length is adjusted by pulling out the leg tube and locking it with an adjacent leg tube with a larger diameter using an appropriate mechanism. In this case, there are roughly two types of locking mechanisms for mutually adjacent leg tubes. That is, a method in which the operating member or the leg tube itself is twisted from the outside to perform mutual tightening, or a tightening member provided on the outside is operated to exert a tightening action on the inner and outer leg tubes. These are collectively called the mutual fastening method, and this mutual fastening method and the inside of the upper end of the leg tube located inside,
A locking pin that protrudes outside the tube under elastic action is installed inside the tube, and when the inner leg tube is fully pulled out, the locking pin is engaged with the lower edge of the outer leg tube adjacent to it. There are two types: pin-locking type.

A conventionally known telescopic leg body using a pin locking method has a locking pin that protrudes outwardly fixed to the leg end of a hairpin-shaped elastic leg piece, and each leg tube is used to pull out or store the elastic leg piece. When the inner leg tube is fully pulled out, the locking pin is inserted into the inner leg tube through a hole made in the leg wall near the upper end by the elastic action of the elastic leg piece. The locking pin protrudes outward, and this protruding locking pin is locked to the lower edge of the outer leg tube to prevent the inner leg tube from being press-fitted into the outer leg tube, and the leg tube is pulled out and joined in the extended state. It was constructed to withstand loads.

The locking pins used in conventional telescopic leg bodies of this type have a conical or hemispherical protruding end surface on the outward protrusion, and therefore not only have a poor locking force between the leg tubes, but also , when you repeatedly extend and contract your legs,
The locking pin is likely to come off from the hole in the tube wall, and as a result, the elastic leg piece may tilt within the leg tube, and even move from its predetermined position, causing the locking pin to protrude from the hole in the tube wall again. There were many failures that resulted in conditions that would have never occurred. Further, even if the locking pin itself performs a predetermined locking action, the portion where the protruding locking pin locks the lower end edge of the outer leg tube is at one point on the circumferential edge of the locking pin, and the lower end Because it contacts the edge, the weight of equipment such as a camera mounted on the leg is supported at this single point, and this load tends to damage the lower edge, especially when the leg contracts. When pressing the top of the locking pin to push the inner leg tube into the outer leg tube, if the locking pin is not pushed in enough and the inner leg tube is pushed into the outer leg tube, There were defects such as damage to the lower edge of the outer leg tube in contact with the locking point, causing it to become dented or to be turned up.

To clarify the conventional technique using the above locking pin method and its defects in more detail with reference to the drawings, FIGS. 1 to 4 show the main parts of the telescopic leg body using the above conventional locking pin method. In the figure, 21, 22, and 23 are leg tubes with slightly different tube diameters, and the leg tube 21 is an inner leg tube with respect to the leg tube 22 into which it is inserted. Also leg pipe 22
becomes the inner leg tube with respect to the leg tube 23 into which it is inserted. In the following explanation, the leg pipe 21 and the leg pipe 22 are
For convenience in explaining the relationship structure between the two and their functions, 21 is referred to as the inner leg tube, and 22 is referred to as the outer leg tube. 31 is a hairpin-shaped elastic leg piece that is housed inside near the upper end of the inner leg tube 21, and is made by bending an elongated steel plate into an inverted U shape.
The ends of the legs have elastic reaction forces that force them to move away from each other. Reference numeral 41 denotes a locking pin fixed to each leg end of the elastic leg piece 31 by caulking or spot welding, and a cylindrical pedestal portion 41' at the base thereof;
The locking pin 41 is fitted into a through hole 15 bored near the upper end of the inner leg tube 21, and is attached to the elastic leg piece 31. Due to the elastic reaction force of the locking pin 4
1 maintains the fitted state in the through hole 51, and
Conversely, the position and posture of the elastic leg piece 31 are maintained by the fitted state of the locking pin 41.

The locking pin 41 used in the conventional telescopic leg body
Because the outward protruding end had a conical or hemispherical protruding end surface, not only was the locking force between the leg tubes poor, but the leg tubes were repeatedly pulled out and pushed in to extend and retract the leg. When the locking pin 41 is easily removed from the through hole 51 in the tube wall, the elastic leg piece 3
1 is also tilted in the leg pipe, and even moved from the predetermined position, and the locking pin 41 is again inserted into the through hole 5 in the pipe wall.
There were many cases of failures that resulted in conditions that could not be recovered from 1.

That is, when the inner leg tube 21 is pulled out with respect to the outer leg tube 22, as shown in FIG.
1 protrudes from the through hole 51 and locks the lower end edge 22' of the outer leg tube 22 as shown in FIG. When the cylindrical pedestal portion 41' is pushed in until it is located inside the inner wall surface of the outer leg tube 22, and the inner leg tube 21 is inserted into the outer leg tube 22 in this pushed state, the second leg tube 21 is inserted into the outer leg tube 22. As shown in the figure,
The locking pins 41, 41 are attached to the inner leg tube 2 while the tip of the cone 41'' is in sliding contact with the inner wall surface of the outer leg tube 22.
1 and slides up inside the outer leg tube 22.
When the operation of pulling out the inner leg tube 21 from the stored state of the inner leg tube 21 with respect to the outer leg tube 22 as shown in the second figure, and then pushing it in and storing it in the opposite direction is repeated, the conical shape of the locking pin 41 is removed. This is caused by irregular forces that are applied during the frictional sliding process between the tip of the tip 41' and the inner wall of the outer leg tube 22, and the effects of dust adhering to the outer wall of the inner leg tube 21 being transferred to the inner wall of the outer leg tube 22. As shown in Figure 3, sometimes the cause is
The locking pin 41 may come off as it moves toward the inside of the inner leg tube 21, and once it comes off, one of the locking pins 41 escapes from its through hole 51, and the elastic leg piece 31
In this case, the user may change the original posture within the leg tube 21, and especially in such a situation, the inner leg tube 21 may be pushed further, or the outer leg tube 22 may be pushed further into the inner leg tube 21.
When the locking pin 41 on the side fitted into the through hole 51 is pulled out, the locking pin 41 on the side fitted into the through hole 51 also comes out of the through hole 51, and the elastic leg piece 31 provided with the locking pins 41, 41 even changes its original position. Even if it becomes like that,
The locking pins 41, 41 no longer fit into the respective through holes 51,
51, and the predetermined locking action cannot be performed. When we investigated the cause of this detachment phenomenon, we found that the main cause is that the locking pin 41 has a cone 41'' at its outer end, and this is pressed by the inner wall of the outer leg tube 22. It has been found that this is due to the fact that spaces P, P are created between the conical surface of the conical body 41'' and the through hole 51 when the elastic leg piece 31 is compressed. That is, when the tips of the locking pins 41, 41 frictionally slide against the inner wall surface of the outer leg tube 22, if an imbalance occurs in the external force exerted on the tips, the conical surface will move against the through hole 51. If an irregular force is further applied, the locking pin 41 easily goes over the edge of the through hole 51. It has become clear that this causes the elastic leg piece 31 to tilt and the locking pin to come off.

On the other hand, even when the locking pin 41 is normally protruding from the through hole 51 and performing the required locking action, the locking portion is between the straight portion of the lower end edge 22' of the outer leg tube 22 and the locking pin 41. One point Q on the cylinder of the pedestal part 41'
Since the load of the camera etc. attached to the upper part of the leg including the outer leg tube 22 is due to the contact with the point Q
In particular, when pushing the inner leg tube 21 into the outer leg tube 22, if the inner leg tube 21 is pushed in with strong force under an insufficient operation of press-fitting the locking pin 41, the Q point The force applied to dents the lower edge 22' of the outer leg tube 22 as shown by the dotted line above,
If the lower end edge is partially turned over and the turned over lower end edge is directed inward, a large load will be applied to the operation of inserting and removing the inner leg tube 21. In addition, the inner leg tube 21
In the case where the outer leg tubes 22 are structured so that they can be twisted in opposite directions about their longitudinal axes, several of the above-mentioned recesses are formed along the lower edge 22'. In some cases, the lower edge 22' was even deformed into a wavy shape.

[Problem to be solved by the invention]

The main purpose of the present invention is to improve such defects. The first object of the present invention is to prevent failures such as the locking pin coming out of its predetermined position and losing the required locking function. The lower edge of the outer leg tube provides a strong counterforce against external forces that act in the direction of pushing the tube into the outer leg tube, and also protects against the load applied during imaging and the abnormal external force that is likely to be applied during contraction and storage. The third purpose is to ensure that the parts are not damaged, and the third purpose is to always allow them to perform smooth and light expansion and contraction operations, thereby increasing their durability. In particular, the need for adaptation to the second purpose is of greater importance when the telescoping leg is used as a monopod than when it is used as a tripod. In other words, when using a tripod, the weight of a heavy object such as a camera mounted on the upper end of the legs is generally distributed over three parts to each leg, but when used as a monopod, the load is divided into three parts. The entire weight is concentrated on one leg, and since photographers tend to hold down the entire camera in order to stabilize the camera during shooting, the load applied to the locking pin, which is the locking part, is This is because the damage increases further and the lower end edge of the outer leg tube that presses the locking pin is more likely to be damaged.

[Means to solve the problem]

In order to achieve these objectives, the present invention:
The shape of the locking pin, the through hole in the tube wall from which the pin protrudes, and the surrounding area have been improved.

That is, a plurality of leg tubes with slightly different pipe diameters, a through hole drilled in the tube wall near the upper end of each leg tube, and a locking pin fitted into each of these through holes are provided at the end. In a pin-locking type telescopic leg body having an elastic leg piece having an elastic reaction force in a direction that causes the locking pin to protrude outside the leg tube, the locking pin is attached to an upper flat surface along the direction in which the locking pin protrudes from the leg tube. The upper flat surface has a depth corresponding to the protruding operation of the locking pin, and the outer edge of the upper flat surface is used as the upper edge to further extend outward. A through hole provided in the pipe wall to form a protruding inclined surface and allow the locking pin forming the prismatic polyhedral body to enter and exit the hole has a cross-sectional shape vertically cut by a plane perpendicular to the protruding direction of the locking pin. The upper frame portion of the inner circumferential surface surrounding the through hole is made to have a matching shape, and the upper frame portion of the inner circumferential surface serves as a sliding guide surface for the locking pin, and the supporting surface is connected to the sliding guide surface of the upper frame portion. A supporting member having a supporting member is provided on the inner wall of the leg tube.

[Effect]

With this structure, when the inner leg tube is fully pulled out relative to the outer leg tube, the lock protrudes from the through hole and engages with the lower edge of the outer leg tube to perform a locking action. The upper flat surface of the retaining pin has a width specific to the upper flat surface and is in contact with the lower edge of the outer leg tube. This will disperse and reduce the load concentrated in one part, and on the other hand, when the protruding part of the locking pin is pushed into the outer leg tube and the inner leg tube is moved within the outer leg tube, the upper part of the locking pin Since a portion of the flat surface always remains engaged with the bearing surface of the bearing member, by sliding it into the inner leg tube and the outer leg tube, the protruding end of the locking pin slides into contact with the inner wall of the outer leg tube. This prevents the locking pin from invaginating into the inside of the medial leg tube.
The locking pin continues to maintain its original position.

〔Example〕

Hereinafter, the fifth preferred embodiment of the present invention will be described.
The telescopic leg tube body shown in FIG. 11 will be described in detail below. These figures show the application of the invention to a monopod in which it functions particularly effectively. Figure 5,
In Figures 9 and 10, 21, 22,...2
5 and 26 are leg tubes, respectively, and the innermost leg tube 21
The outermost leg tubes 26 have slightly different tube diameters, and are inserted and accommodated inside one after another. A leg tube 27 located on the outside of these leg tubes 21, 22, .
1 and is housed inside it, but it is not pulled out to the exterior cylindrical body 111. The leg tubes 21, 22, . . . 25, 26 have elastic leg pieces 31, 32, . . . 35, 3 near their upper ends.
6 is installed inside each of these elastic leg pieces,
Locking pins 61, 62, ... 65, 6 at both leg ends, respectively
6 is provided. The fact that each of these elastic leg pieces is a hairpin-shaped leg piece made by bending a narrow steel plate into an inverted U-shape is not particularly different from the case of a known telescopic leg body. Each leg pipe 21, 2
2, . . . 25, 26 are provided with through holes 71, 72, .
The locking pins 61, 76 of each leg pipe 21, 22, . . . 25, 26 are bored through the respective pipe walls.
62, . . . 65, 66 are the positions where these leg tubes are fully drawn out, and these through holes 71, 72, .
The fact that the legs protrude sufficiently from 75 and 76 is the same as in the case of the conventional telescopic legs. However, in the case of the present invention, these locking pins 61, 62,...
... Both 65 and 66 have a cross-sectional shape in a vertical plane perpendicular to their protruding direction, which is approximately a quadrilateral, a similar polygon, or other external shape, and it is clear from the shape that they have a conventionally well-known circular cross-section. Furthermore, these locking pins 61, 62,...6
Through holes 71, 72, . . . for protruding 5, 66
The holes 75 and 76 also differ from conventional circular through holes in that they have an outer shape that matches the cross-sectional shape of each locking pin. In the illustrated example, as can be seen from FIG. 7, both the locking pin and the through hole from which it projects have a substantially square cross-sectional shape. On the other hand, as shown in FIG. 6, the portions corresponding to the upper sides of each locking pin are upper flat surfaces 61a, 62a, .
a, and the depth of these upper flat surfaces corresponds to the required protrusion length. In addition, the outer surface connected to each upper flat surface is
Inclined surfaces 61b, 62b, ... 65 whose respective outer edges are used as upper edges and further protrude outward.
b, 66b are given. With such a configuration, the upper frame portions 71a, 72a, . . . 75 of each through hole
a and 76a are the upper flat surfaces 61 of each locking pin.
a, 62a...65a, 66a are formed with straight edges so as to be in sliding contact with them. The inner portions continuous with these upper frame portions 71a, 72a, . Supporting surfaces 81a, 82a,
...Supporting member 8 comprising 85a and 86a, respectively
1, 82, . . . 85, 86 are provided. Therefore, each bearing surface 81a, 82 of these bearing members
a,...85a, 86a are the upper flat surfaces 61a, 62a,...65 of each corresponding locking pin.
Even when the respective locking pins are fully pushed into sliding contact with the upper flat surfaces 61a, 62a, . . . 6
It is always in contact with parts of 5a and 66a. In the illustrated example, each of the supporting members 81, 82, . . . 85, 86 is
Respective through holes 71, 72, ... 75, 76 of each leg pipe
Upper edges 71a, 72a,...75a, 76
These are separately fixed to the inner wall of each leg tube in contact with a, but these may be fitted and fixed to the inner wall of each leg tube as an annular member as shown in Fig. 8, or in some cases. is formed by punching out when forming each leg tube (see Fig. 13) or by cutting (see Fig. 12), and is formed together with the leg tube as an annular part that protrudes inward. You may.

Each locking pin has the above-mentioned upper flat surface 61a,
As a result of providing the inclined surfaces 62a, 65a, 66a and the subsequent inclined surfaces 61b, 62b, 65b, 66b, each vertical cross section in the direction intersecting the vertical plane perpendicular to the protruding direction of the locking pin. The cross-sectional shape of the locking pin is approximately trapezoidal as shown in FIG.
5c and 66c are advantageous for smoothly protruding and pushing in each locking pin. In particular, such rounded or truncated surfaces 61c, 62
Forming the pins c, . . . 65c, 66c is useful in softening the contact with the fingertip surface when each locking pin is pushed in to shorten each leg tube. In addition, each of the elastic leg pieces 31, 32, .
...When 65 and 66 protrude outward from each leg tube, the movement of each of these locking pins is centered at the point where the central axis of each leg tube intersects with the bent portion of each elastic leg piece. Considering that the movement will be in an arc, it is more desirable that the bottom surface of the lower end of each locking pin be made low on the inside and high on the side with the truncated surface, along this arc. Then, each through hole 71, 72,
...lower frame portions 71b, 72b, . . . of 75, 76
75b, 76b are the lower edges 61d, 6 of each truncated surface.
2d, ... 65d, 66d pass along the locus of the circular motion, or along the tangential direction of this circular motion, make a certain angle (angle θ in Fig. 8) with respect to the horizontal plane. It is desirable to open the hole at the same angle, but this angle is
It depends on the specific height of 2,...35,36, but it is usually about 1°30' to 2°.

In addition, 12 in the figure indicates each leg pipe 21, 22,
... 25, 26 is a retaining ring fitted on the outer periphery of the upper end, and 13 denotes each of the leg pipes 22, 23, . . .
It is a retaining cylinder fitted to the lower end of the inner wall of each leg pipe 21, 22, . . . 25, 26.
When pulled out, the lower peripheral surface of the retaining ring 12 and the upper peripheral surface of the retaining tube 13 define the pulling limit of each leg tube and prevent each leg tube from coming off. be. In order to simplify assembly, these retaining ring 12 and retaining tube 13 are partially provided with cleavage (not shown) along the axial direction to allow compression when reducing the diameter. 12 is given a return elasticity in the direction of enlarging the diameter, and the retaining cylinder 13 is given a return elasticity in the direction of reducing the diameter in advance, so that the return action after fitting is changed to the locking action due to mutual collision. The structure is the same as that normally used for this type of telescopic leg body. In addition, 14 is the innermost leg pipe 2
A support called a pedestal is integrally fitted into the end of the opening at the bottom of 1, and in the case shown, a recess 15 is formed at the bottom end to allow the monopod to stand on the floor, ground surface, etc. It is designed to exhibit an adsorption effect that prevents slippage due to the load applied under the condition.

According to the telescopic leg body of the present invention having such a configuration, the stone protrusion 14 can be moved from the contracted and stored state shown in FIG.
Alternatively, by pulling the lower end of the leg tube 21, the leg tube 21 is pulled out as shown in FIG.
2, 23, ... 25, 26 depend on the state of sliding friction between the leg tubes located next to each other,
The legs are pulled out one after another, and sufficient pulling out of each leg tube ends when the retaining ring 12 and retaining tube 13 collide with each other. FIG. 9 shows a state in which the retaining ring 12 abuts against the retaining tube 13 and the leg tube 21 is fully pulled out from the leg tube 22. When the leg tube 21 is pulled out to this pull-out position, the elastic reaction force of the elastic leg pieces 31 causes the tip ends of the locking pins 61, 61 to
The locking pin 6 slides by pressing against the inner wall of the locking tube 13 fitted into the leg tube 22 and the inner wall of the retaining tube 13 fitted into the leg tube 22
1 and 61 are the leg pipes 2 at once in the through hole 71.
The upper flat surface 61a of the leg tube 22 protrudes outwardly, and its upper flat surface 61a protrudes while sliding against the lower end edge 22' of the leg tube 22 located further outside, and engages with this to perform the required locking action. In this case, the protrusion of the locking pin 61 means that the mounting base of the lower locking pin 61 of the elastic leg piece 31 is attached to the support member 8.
1, and the load applied to the leg pipe 22 from above is applied to the lower end edge 22' and the upper flat surface 61a having the width of the locking pin 61 engaged therewith, and further, It reaches the lower frame part 71b of the through hole 71 via the locking pin 61, and the inner leg pipe 21
will be reliably communicated. Similarly, at the limit of pulling out the leg tube 22, the locking pin 62 performs a locking action on the lower edge of the leg tube 23, and for each locking pin of each leg tube, the locking pin 62 acts on the lower edge of the outer leg tube. It performs the necessary locking action and gives the entire leg body in the extended state a strong, rigid uprightness that is difficult to bend.

In the telescopic leg body of the present invention, all the locking pins of each part are the upper flat surfaces 61a, 62a, . . . 65
a, 66a securely captures and locks the lower edge of the adjacent leg pipe, but this locking action does not affect each leg pipe 2.
2, 23, . . . 25, 26 with deep flat surfaces 61a, 62a, . . . 65a,
66a, and when viewed from the side as shown in FIG.
Since the locking action is performed over a width rather than a single point engagement, it acts as a large counterforce against loads and external forces that act in the direction of pushing the inner leg tube into the adjacent outer leg tube. As a result, it acts as a strong resistance force, preventing the load from being concentrated locally.
As is clear from the comparison with FIG. 4, there is no need for damage such as denting or rolling up the lower edge of the leg tube.

In addition, when each leg tube is inserted into an adjacent outer leg tube to make it in a contracted state convenient for carrying and storing, the locking pins, for example 61, protruding in opposite directions are squeezed, respectively. Resisting the elastic reaction force of the elastic leg piece, push the protruding end edge inward from the inner wall surface of the adjacent outer leg tube 22, and the rear inner leg tube 21
is pushed into the leg tube 22 on the outside. At that time, the locking pin 61 has an inclined surface 61b that is connected to the outer edge of the upper flat surface 61a and has this as the upper edge. Therefore, unlike the conventional example in which the tip of the cone is pinched, the fingertip surface does not feel pain, and there is no difficulty in pushing the locking pin 61 with sufficient pressure. . Furthermore, even if the inner leg tube 21 is pushed into the outer leg tube 22 without pushing the locking pin 61 sufficiently, at that time, the inclined surface 61b may be pushed into the lower end edge 22' of the outer leg tube 22. This pressurizing force is applied by the inclined surface 61b, and a horizontal component force acts on the locking pin 61 as a force toward the inside of the leg tube 22, prompting the locking pin 61 to be pushed in, Make operations smooth and easy. Fig. 10 shows part of the process for quickly retracting the legs by storing each leg tube, but this figure shows only the inner leg tube 2.
1 is pushed into the outer leg tube 22, the outer leg tube 22 is first pushed into the leg tube 23 located outside of it. In such a case, apart from the operation of squeezing the locking pin 61 of the inner leg tube 21 and pushing it into the leg tube 21 through the through hole 71, the inner leg tube 21
By pushing the locking pin 61 in as it is, the locking pin 61 first moves to the inclined surface 61b near its protruding end.
collides with the lower end edge 23' of the leg tube 23, and the same component force as in the above description acts in the direction of pushing the locking pin 61, causing the leg tube 2 to enter the inside of the leg tube 23.
1 is a locking pin 61 as shown in FIG.
The accommodation operation proceeds while the leg tube 23 passes under the lower end edge 23' and slides into contact with the inner wall thereof or the inner surface of the retaining tube 13 fitted to the inner wall. In this way, when sliding action occurs between the locking pin 61 and the leg tube 23 that is one outside of the adjacent leg tube 22, the elastic leg piece 31 is slightly bent in this state, and the locking pin 61 is bent slightly. Since the pin 61 is slightly pushed into the through hole 71, the subsequent push-in operation of the inner leg tube 21 pushes the locking pin 61 into the upper flat surface 61a located above the inclined surface 61b. The nearer portion is pressed against the lower end edge 22' of the leg tube 22, and a similar component force acting thereon allows the locking pin 61 to be locked without having to be pressed and pushed deep into the through hole 71. The stop pin 61 can then be brought inside the leg tube 22. This explanation has been made as a premise for quickly retracting the telescopic leg body. According to this operation method, the final stage locking pin, for example 66a, is compressed and the leg tube located outside of the locking pin 66a is compressed. For example, after slightly pushing in the leg tube 26 which has a locking pin 66a inside 27, if you grasp the innermost leg tube 21 and continue to push it in,
A locking pin 65 installed inside the next leg pipe 25
The inclined surface 65b automatically slips into the leg tube 27 due to the force exerted by the lower edge of the leg tube 27, and then the locking pin is slightly compressed by the inner wall of the leg tube 27. 65a is the lower end edge 26' of the leg tube 26
, the pins 64a, 63a, 62a, and 61a are released in the order of locking pins 64a, 63a, 62a, and 61a, respectively. This quick storage function makes it possible to push and accommodate the required leg tube without having to manually pinch each locking pin. This is because an inclined surface is formed in a manner that is continuous with the outer edge of the upper flat surface that serves as the locking portion and projects further outward with the same edge as the upper edge.

By the way, whichever method is used to push and accommodate the leg tubes, each locking pin slides with its protruding end while rubbing against the inner wall of the leg tube located on the outside, and each leg tube advances one after another. During these operations, even if an irregular external force is applied to any of the locking pins, according to the present invention, a portion of the deep upper flat surface is always retracted. Since it is in contact with the support surface of the support member, the locking pin is supported without any gap, and no acting force acts in the direction of tilting the elastic leg piece, so the locking pin can be removed from the through hole. This prevents the locking pin from coming off from the through hole without causing any change in posture relative to the elastic leg piece.

In addition, in the present invention, in order to more actively prevent changes in the posture and position of the elastic leg piece provided with the locking pin, some troublesome work has been added to the machining process in the above-described embodiment. For example, the lower part of the elastic leg piece 31 near the leg end is bent twice in opposite directions, and these bent parts and the upper flat surface 61a of the locking pin 61 are bent. It can also be configured to surround the support member 81 (as shown in Figure 13). When the lower part of the elastic leg piece is configured in this way, the piece does not have an inverted U-shaped outer shape but a vertically flat Ω-shaped outer shape.

In the above embodiments, the present invention is applied to a monopod where its characteristic functions are best exhibited, but it goes without saying that this unique structure can also be applied to a tripod. It goes without saying that similar effects can be achieved by using various designs for each member in terms of shape or arrangement within the scope of the gist of the invention described in the claims. Of course, changes can be made.

〔effect〕

In the telescopic leg body according to the present invention, even if the leg body is extended and retracted violently, the locking pin will not come out of its predetermined position and lose its locking function, and once the locking pin is When it protrudes outside the tube and is locked to the lower edge of the outer leg tube to produce a locking action,
The wide upper flat surface engages with the lower edge, and its locking function is very good, and the external force under load or operation in a direction that pushes the inner leg tube into the outer leg tube. Even if the locking pin is activated, a strong counter force is exerted, and damage to the lower end edge of the leg tube is prevented. This is helpful in allowing the legs to quickly contract, and as long as they are handled in accordance with the prescribed procedures, all operations will be carried out smoothly and easily, ensuring long durability over time, and ensuring that the desired results are maintained. You can achieve your goal.

[Brief explanation of drawings]

1 to 3 are schematic cross-sectional views illustrating the leg tube locking portion, its function, and tendency in a conventionally known telescopic leg for photographing. FIG. 4 is a schematic side view of a leg tube locking portion in a conventionally known telescopic leg body for photographing. Fifth
The figure is a longitudinal sectional front view showing the whole when the telescopic leg body for photography according to the present invention is applied to a monopod.
The figure shows a state in which all the extendable and retractable leg tubes constituting the leg body are housed in adjacent leg tubes. 6th
The figure is an enlarged front view of the characteristic locking pin of the present invention, FIG. 7 is a side view of the same, and FIG. 8 shows details of the locking pin, the inner and outer leg pipes, and the support member in the locked state. FIG. 9 is a partially cutaway enlarged front view showing the main part of the process of pulling out the innermost leg tube from the state shown in FIG. 5 and using the leg body for extension, FIG. 10. 11 is an enlarged partially cutaway front view of the main part showing a part of the continuous storage process in which the leg tubes of the leg bodies in the extended state are contracted and each leg tube is accommodated in adjacent leg tubes; The figure is a schematic side view of the leg tube locking part in the telescopic leg body according to the present invention, and FIG. 12 is a partially longitudinal enlarged front view showing an example in which a support member is formed by cutting a part of the upper end of the leg tube. 13 are partially longitudinal enlarged front views showing an example in which a support member is formed by extruding a part of the upper end of the leg tube. 21,22,...25,26...leg tube, 27...
... Leg tube, 31, 32, ... 35, 36 ... Elastic leg piece, 61, 62, ... 65, 66 ... Locking pin,
61a, 62a,... 65a, 66a... Upper flat surface, 61b, 62b,... 65b, 66b...
Inclined surface, 61c, 62c, ...65c, 66c...
...Truncated surface, 61d, 62d, ...65d, 66d
... lower edge of truncated surface, 71, 72, ... 75, 76
...Through hole, 71a, 72a, ...75a, 76a
... Upper frame part of the through hole, 71b, 72b, ...75
b, 76b... lower frame part of the through hole, 81, 82,...
85, 86...Supporting member, 81a, 82a,...
85a, 86a...Supporting surfaces of supporting members.

Claims (1)

[Scope of Claims] 1. A plurality of leg pipes having slightly different pipe diameters, a through hole drilled at a position near the upper end of each leg pipe, and a connecting member whose outer end is inserted into each of the through holes. an elastic leg piece that has a stop pin at its end and has elasticity in a direction that causes the stop pin to protrude toward the outside of the leg tube, and the stop pin has an upper flat surface that extends in the direction in which the stop pin projects. The upper flat surface has a depth corresponding to the protruding operation of the locking pin, and an inclined surface that further protrudes outward with its outer edge as the upper edge. , the through hole is opened in a shape that matches the cross-sectional shape taken vertically by a polyhedral surface perpendicular to the protruding direction of the locking pin, and an upper frame of the inner circumferential surface surrounding the through hole is formed. A retaining member having a bearing surface continuous with the sliding guide surface is provided on the inner wall of the leg tube, and the inner leg tube is fully pulled out from the outer leg tube. In this state, the upper flat surface of the locking pin protruding from the through hole performs a locking action to engage with the lower edge of the outer leg tube, so that when the inner leg tube moves within the outer leg tube, Even when the locking pin that is in sliding contact with the inner wall of the outer leg tube is pressed against the inner wall of the outer leg tube by the elasticity of the elastic leg piece, a part of the upper flat surface of the locking pin is A telescopic leg for photographing, characterized in that it maintains engagement with the support surface of the support member. 2. According to claim 1, the locking pin has a quadrilateral outer shape in a plane orthogonal to the protruding direction thereof, and a vertical cross-sectional shape intersecting the orthogonal plane is trapezoidal. Extendable legs for photography. 3. The telescopic leg body for photographing according to claim 1, wherein the locking pin has a truncated surface formed by cutting a part of the sloped surface of the locking pin. 4. The telescopic leg for photographing according to claim 1, wherein the support member is formed of an annular body along the inner wall of the leg tube and is fitted into the inner wall. 5. The telescopic leg body for photographing according to claim 1, wherein the support member is formed by stamping and molding near the upper end of the leg tube. 6. The telescopic leg for photographing according to claim 1, wherein the support member is formed to project integrally with the leg tube by cutting a material that constitutes the leg tube. 7. The telescopic leg for photographing according to claim 1, wherein the through hole is formed at a lower frame portion thereof with an inclination that follows the trajectory of the circular arc movement of the protruding locking pin. body. 8 The elastic leg piece is birefringent in opposite directions near the end portion having the locking pin, and the supporting member is surrounded by these bent portions and the upper flat surface of the locking pin. The telescopic leg body for photographing according to claim 1, characterized in that the telescopic leg body for photographing is made as follows.