The present invention relates to a stick provided with a collapsible mechanism.

Conventionally, as sticks used for assisting in walking, there have been known sticks collapsibly structured to be carried in tote bags or the like when not in use. As a structure enabling a stick to be collapsible, there has been known a structure in which the shaft portion of the stick is divided into a plurality of pipes, through which a connecting cord having elasticity such as rubber is passed, to make the pipes tightly fitted to each other using the elasticity of the connecting cord. An example of such a collapsible stick using an elastic cord is disclosed in Patent Document 1.

In addition, as a structure for enabling a stick to be collapsible, Patent Document 2 discloses a structure in which, in connecting a plurality of pipes with each other, respective pipes are made tightly fitted to each other by a biasing force of a spring, by use of the spring and a wire instead of an elastic cord. In the collapsing mechanism disclosed by Patent Document 2, for each connecting portion, a wire having wire retaining rings attached to both ends thereof is biased by a compression spring 9 while the connection is kept, and, when the connection is released, the biasing force of the compression spring is removed by staying the compression spring 9 in the compressed state, to allow the connection between the pipes to be released (refer to FIG. 4 etc. of the cited Document 2).

• Patent Document 1: JP Utility Model Register No. 3156004
• Patent Document 2: JP Patent Laid-Open No. 2004-329839

The collapsing mechanism of the stick disclosed in Patent Document 1 uses a single connecting cord 55 having elasticity, to couple together from a first pipe member 3 to a second pipe member 11 via a first intermediate pipe member 5, a second intermediate pipe member 7 and a third intermediate pipe member 9. Therefore, in transition from the collapsed state to the connected state, the elastic force of the connecting cord acting between the first pipe member 3 and the second pipe member 11 enables the first intermediate pipe member 5, the second intermediate pipe member 7, and the third intermediate pipe member 9 to be connected at once. However, in the case of such a configuration, since the elastic force is kept exerted on the connecting cord 55 even in the collapsed state, the elastic force acts, in the collapsed state as shown for example in FIG. 2 of the cited Document 1, to urge the pipes to return to the in-line arrangement and, when an attempt is made to bring the structure into the connected state, the pipe members are strongly moved toward the in-line arrangement, to put the user at the risk of injury.

Unlike the stick described in Patent Document 1, the collapsing mechanism of the stick described in Patent Document 2 does not use a connecting cord having elasticity for connecting the respective pipes. For this reason, when an attempt is made to bring the structure into the connected state, the pipe members are not moved toward the in-line arrangement as in the case of the stick described in Patent Document 1, and thus does not put the user at the risk of injury. However, since connecting mechanisms are individually provided in the connecting portions of the stick described in Patent Document 2, when the stick is to be brought into the connected state, it is necessary for the user to insert the connecting portions one by one, which is troublesome.

The present invention has been made to solve these problems, and it is an object of the present invention to provide a collapsible stick in which individual parts are prevented from being uncontrollably moved by elasticity of a connecting cord in transition from the collapsed state to the connected state and which can be brought into the connected state by a simple operation.

In order to attain the above object, the collapsible stick of the present invention includes a first tube having a grip, a second tube having a ferrule, and at least one intermediate tube arranged between the first tube and the second tube, wherein the first tube has a locking member having a locking portion with flexibility, a wire member one end of which is attached to the locking member and other end of which is attached to the second tube, a spring member urging the locking member toward one side, a stopper portion having a lock receiving portion, and an unlocking button having a pressing portion and arranged in the vicinity of the stopper portion, and a narrowest space in the stopper portion is narrower than the locking portion of the locking member, so that, in a movement toward other side against a biasing force of the spring member, the locking member bends the locking portion during it passing through the narrowest space in the stopper member and restoration of the locking portion makes it engaged with the lock receiving portion, and, where the locking member is stopped by the stopper portion, the unlocking button releases the lock by pressing the locking portion of the locking member via the pressing portion.

In this case, between the first tube and the intermediate tube, there is provided a second wire having fixing members attached to both ends thereof, and each of the connecting portions formed on the end portion of the first tube and the end portion of the intermediate tube is provided with a retaining member through which the wire and the second wire are inserted and a contact portion that can come into contact with the retaining member. In the connection released state, it is preferable that the intermediate tube is made to hang from the first tube by the fixing members, which are attached to the both ends of the second wire and make the connecting portions hang on each other via the retaining members and the contact portions.

In any of the above cases, it is preferable that a constant load spring be used as the spring member.

According to the present invention, since the configuration is made to bias the wire which connects the first tube having the grip and the second tube having the ferrule by use of the spring member provided in the first tube and to allow the locking member attached to the wire to be locked, it is possible to obtain a collapsible stick in which each component is not uncontrollably moved by the elasticity of the spring member biasing the wire at the time of changing from the collapsed state to the connected state and which can be brought into the connected state by a simple operation.

• FIG. 1. is an overall view that shows the connected state of a collapsible stick according to the present invention.
• FIG. 2 is a view that shows the interior of a first tube 1 in the connected state of the collapsible stick according to the present invention.
• FIG. 3 is a view that shows the structure of the connecting portion between the first tube 1 and an intermediate tube 3 of the collapsible stick according to the present invention.
• FIG. 4 is a view that shows the structure of a second tube 2 of the collapsible stick according to the present invention.
• FIG. 5 is a view that shows the interior of the first tube 1 in the connection released state of the collapsible stick according to the present invention.
• FIGs. 6 are overall views of the collapsible stick according to the present invention, where (a) shows the connection released state and (b) shows the collapsed state.

The mode for carrying out the present invention will be described in detail with reference to the drawings.

First, the structure of the collapsible stick according to the present invention will be described with reference to FIG. 1. The collapsible stick according to the present invention includes a first tube 1 having a grip, a second tube 2 to which a rubber ferrule is attached, and intermediate tubes 3, 4 disposed between the first tube 1 and the second tube 2. The first tube 1, the second tube 2, and the intermediate tubes 3, 4 are hollow inside.

Next, the internal structure of the first tube 1 will be described with reference to FIG. 2. In the first tube 1, a spring member 5 is disposed near the grip. The spring member 5 is formed of a combination of two Conston (registered trademark, hereinafter omitted) springs 5a, 5b, which are constant load springs, and a locking member 6 is attached to the tip of each of the Conston springs. The locking member 6 has a locking tab 6a at the center thereof, and is connected to the Conston springs 5a, 5b at one end thereof and to a wire 7 at the other end thereof. These two Conston springs 5a, 5b in the state shown in FIG. 2 are in the most reeled-up state. Inside the first tube 1, a stopper portion 1a is formed so that the locking tab 6a rests thereon to be stopped. The narrowest space in the stopper portion 1a is designed to be narrower than the lateral extension of the locking tag 6a of the locking member 6 so that the locking member 6 passes by the stopper portion 1a while bending the locking tab 6a.

In the vicinity of the stopper portion 1a, an unlocking button 8 is provided. The unlocking button 8 has a head portion 8a projecting outside the first tube 1 and a tip end portion 8b inside the first tube 1. The unlocking button is urged in its entirety by a spring 8c in the direction for jumping outward with respect to the first tube 1 but the tip end portion 8b abuts on the inside wall of the first tube 1 to serve as a retainer. When the unlocking button 8 is pressed, it is pushed into the first tube 1 against the biasing force of the spring 8c, and the tip end portion 8b moves in the radial direction toward the center of the first tube 1. After that, when the pushing of the unlocking button 8 is ceased, it moves outward with respect to the first tube 1 owing to the biasing force of the spring 8c, but stops where the tip end portion 8b abuts on the inside wall of the first tube 1.

Next, the structure of connecting portions between the first tube 1, the second tube 2, and the intermediate tubes 3, 4 will be described with reference to FIG. 3. While FIG. 3 shows the structure of the connecting portion between the first tube 1 and the intermediate tube 3, the structure of the connecting portion between other tubes is also the same. At the intermediate-tube-3-side end portion of the first tube 1, a connecting portion 1b with a concave shape is formed. The connecting portion 1b has a guide portion 1b-1. Inside the first tube 1, a contact portion 1c is formed in the vicinity of the connecting portion 1b. The guide portion 1b-1 is formed as a slope having the same angle as a taper portion 3a-1 of a later-described connecting portion 3a. The contact portion 1c is formed to have an inside diameter smaller than the inside diameter of the first tube 1.

At the first-tube-1-side end portion of the intermediate tube 3, a connecting portion 3a with a convex shape is formed. The connecting portion 3a has a tapered portion 3a-1 and a tapered portion 3a-2. Inside the intermediate tube 3, a contact portion 3b is formed in the vicinity of the connecting portion 3a. As described above, the tapered portion 3a-1 is a slope having the same angle as the guide portion 1b-1, and when the first tube 1 and the intermediate tube 3 are connected, the guide portion 1b-1 and the tapered portion 3a-1 are in surface contact with each other. Further, the contact portion 3b is formed to have an inside diameter smaller than the inside diameter of the intermediate tube 3.

Inside the first tube 1, a retaining member 9 is arranged closer to the center of the first tube 1 than the contact portion 1c is. The retaining member 9 has two holes 9a, 9b, and its outside diameter is smaller than the inside diameter of the first tube 1 and larger than the inside diameter of the contact portion 1c. The wire 7 is inserted through the hole 9a of the retaining member 9, and a wire 10 is inserted through the hole 9b.

Inside the intermediate tube 3, a retaining member 11 is arranged closer to the center of the intermediate tube 3 than the contact portion 3b is. The retaining member 11 has two holes 11a, 11b, and its outside diameter is smaller than the inside diameter of the intermediate tube 3 and larger than the inside diameter of the contact portion 3b. The wire 7 is inserted through the hole 11a of the retaining member 11, and the wire 10 is inserted through the hole 11b. Unlike fixing members 12, 13 which will be described later, these retaining members 9, 11 are not fixed to the two wires 7, 10. As understood from FIG. 3, the wire 10 is shorter than the wire 7, and there are provided in total two such wires 10, one each for the connecting portion between the first tube 1 and the intermediate tube 3 and the connecting portion between the intermediate tube 3 and the intermediate tube 4.

The wire 10 has fixing members 12, 13 fixed at both ends thereof, that is, at a position closer to the center of the first tube 1 than the retaining member 9 is and at a position closer to the center of the intermediate tube 3 than the retaining member 11 is. The outer diameters of these fixing members 12, 13 are larger than the holes 9b, 11b of the retaining members 9, 11. Further, these fixing members 12, 13 are fixed to the wire 10.

The structure of the connecting portion between the intermediate tube 3 and the intermediate tube 4 is also similar to the structure of the connecting portion between the first tube 1 and the intermediate tube 3. Although detailed explanation is omitted, a connecting portion 3c with a concave shape is formed at the intermediate-tube-4-side end portion of the intermediate tube 3 and a connecting portion 4a with a convex shape is formed at the intermediate-tube-3-side end portion of the intermediate tube 4, as shown in FIG. 6(a) etc. The connecting portion 3c has a guide portion 3c-1, and the connecting portion 4a has tapered portions 4a-1, 4a-2. A contact portion is formed inside the intermediate tube 3 in the vicinity of the connecting portion 3c and a contact portion is formed inside the intermediate tube 4 in the vicinity of the connecting portion 4a, but showing them is omitted. Further, similar to the structure of the connecting portion between the first tube 1 and the intermediate tube 3, inside the intermediate tubes 3, 4, retaining members 9, 11 are arranged and the wire 7 and the wire 10, which has fixing members 12, 13 attached to both ends thereof, are inserted through each of the retaining members, but showing them is omitted, also.

The structure of the connecting portion between the intermediate tube 4 and the second tube 2 is different from the structure of the connecting portions between other tubes. First, the structure of the connecting portion of the intermediate tube 4 will be described. At the second-tube-2-side end portion of the intermediate tube 4, a connecting portion 4b with a concave shape is formed. The connecting portion 4b has a guide portion 4b-1. Further, inside the intermediate tube 4, a contact portion is formed in the vicinity of the connecting portion 4b, but showing it is omitted. Unlike the structure of the other connecting portions, no retaining member is arranged inside at the second-tube-2-side end portion of the intermediate tube 4. In addition, the wire 10 is not arranged, and the wire 7 is merely passed through.

Next, the structure of the second tube 2 will be described with reference to FIG. 4. In the second tube 2, two tubes are fitted in and out each other to form one tube. Of these two tubes, the tube 2A on the intermediate-tube-4 side has the same outside diameter and inside diameter as those of the first tube 1 and the intermediate tubes 3, 4. The other tube 2B is arranged to fit on the tube 2A, and the inside diameter thereof is substantially the same as the outside diameter of the tube 2A.

At the intermediate-tube-4-side end portion of the tube 2A, a connecting portion 2Aa with a convex shape is formed. The connecting portion 2Aa has a tapered portion 2Aa-1 and a tapered portion 2Aa-2. Inside the tube 2A, a wire attachment portion 2Ab is provided, and an end of the wire 7 is attached thereto.

The tube 2B is provided with a plurality of holes 2Ba. The tube 2A is provided with a button 2Ac that can be fitted in the holes 2Ba, where the button 2Ac is urged radially outward with respect to the tube 2A by a spring 2Ad. Since the tubes 2A, 2B are configured in such a way, the length of the entire second tube 2 is adjustable depending on where to insert the button 2Ac among the plurality of holes 2Ba of the tube 2B. While the button 2Ac is inserted in a hole 2Ba, the tubes 2A, 2B do not move either in the angular direction or in the longitudinal direction with the tube 2B being locked by the button 2Ac. In a situation where a change of the length of the entire second tube 2 is desired, pushing in the button 2Ac to release the locking of the tube 2B and aligning the button 2Ac with an appropriate hole 2Ba causes the button 2Ac to be inserted in the hole 2Ba by the biasing force of the spring 2Ad. By doing so, it is possible to adjust the length of the entire second tube 2, and, accordingly, to adjust the length of the entire collapsible stick according to the present invention.

Next, the method of using the collapsible stick according to the present invention will be described with reference to FIGs. 1, 2, 5, and 6. The collapsible stick according to the present invention has, as shown in FIG. 1, the individual tubes from the first tube 1 to the second tube 2 connected together in the connected state. To bring it from this state to the collapsed state, firstly, one should pull the second tube 2 in the longitudinal direction of the stick while holding the first tube 1. This action also causes the wire 7, which is attached, at one end thereof, to the wire attachment portion 2Ab of the tube 2A of the second tube 2, to be pulled simultaneously. Therefore, the Conston springs 5a, 5b are pulled via the locking member 6 to which the other end of the wire 7 is attached. In this way, the locking member 6 is moved downward in FIG. 2 against the tension of the Conston springs 5a, 5b. Then, the locking member 6 is to pass through the stopper portion 1a while bending the locking tab 6a. When the locking tab 6a of the locking member 6 completes passing through the stopper portion 1a, the locking tab 6a returns to the original shape by the restoring force. When the operation of pulling the second tube 2 is stopped, the locking member 6 slightly returns upward in FIG. 2 owing to the tension of the Conston springs 5a, 5b, but the movement is stopped by the locking tab 6a coming into contact with the rim of the stopper portion 1a. In this way, the locking member 6 is locked, to be in the state shown in FIG. 5. FIG. 6(a) shows the state of the stick at this time.

In the connection released state shown in FIG. 6(a), since the end of the wire 7 is fixed to the wire fixing portion 2Ab, the second tube 2 is hung via the wire 7. On the other hand, the intermediate tube 3 is not hung via the wire 7 because the wire 7 is inserted through the hole 11a of the retaining member 11 but is not fixed thereto. In the connecting portion between the first tube 1 and the intermediate tube 3, since the wire 10 with the fixing members 12, 13 being fixed at the both ends thereof is inserted through the holes 9b, 11b of the retaining members 9, 11, in the state shown in FIG. 6(a), the contact portion 1c of the first tube 1 comes into contact with the retaining member 9 and the retaining member 9 comes into contact with the fixing member 12 and, at the same time, the contact portion 3b of the intermediate tube 3 comes into contact with the retaining member 11 and the retaining member 11 comes into contact with the fixing member 13, so that the intermediate tube 3 is hung from the first tube 1 via the wire 10. In the similar manner, the intermediate tube 4 is also hung from the intermediate tube 3 via the wire 10.

Folding back individual tubes in order brings the stick from the connection released state shown in FIG. 6 (a) to the collapsed state shown in FIG. 6(b).

To bring the stick from the collapsed state to the connected state, one should return the position of each tube from the state shown in FIG. 6(b) to the state shown in FIG. 6(a). After that, pressing the unlocking button 8 brings the stick into the connected state.

Actions occurring when the unlocking button 8 is pressed will be described with reference to FIGs. 1, 2, 5, and 6. When the unlocking button 8 is pressed, its tip end portion 8b presses and bends the locking tab 6a of the locking member 6. When the locking tab 6a is bent and separated from the rim of the stopper portion 1a, the locking member 6 is drawn upward in FIG. 5 by the tension of the Conston springs 5a, 5b. Then, when the locking tab 6a completes passing through the stopper portion 1a to restore the original shape and reeling up of the Conston springs 5a, 5b is stopped, the stick is returned to the state shown in FIG. 2.

At this time, the second tube 2 also is drawn up by the tension of the Conston springs 5a, 5b via the wire 7 attached to the locking member 6. In this situation, the connecting portion 2Aa of the tube 2A of the second tube 2, the connecting portion 4a of the intermediate tube 4, and the connecting portion 3a of the intermediate tube 3 are smoothly connected together even if drawn up in a rush, because the tapered portions 2Aa-2, 4a-2, 3a-2 are guided by the guide portions 4b-1, 3c-1, 1b-1, respectively. Then, the tapered portions 2Aa-1, 4a-1, 3a-1 make surface contact with the guide portions 4b-1, 3c-1, 1b-1, respectively, to complete connections between the respective tubes, and the stick is returned to the connected state.

As described above, since the tension of the wire 7 is not applied to the collapsible stick according to the present invention in the connection released state shown in FIG. 6(a), the operation of folding the tubes and the operation of arranging the tubes in line can be very easily conducted, which is advantageous.

Further, since the collapsible stick according to the present invention can be brought into a connected state from the connection released state only by pushing the unlocking button 8, it does not require troublesome assembly and is very easy to handle, which is advantageous.

Further, since the intermediate tube 3 is suspended from the first tube 1 and the intermediate tube 4 is suspended from the intermediate tube 3 in the connection released state shown in FIG. 6(a) with the distances between the tubes being kept, the collapsible stick according to the present invention is easy to handle when to be folded, which is advantageous. In the case where such a mechanism for maintaining the distance between the tubes is not provided, when the second tube 2 is pulled, the intermediate tube 4 moves while being connected to the second tube 2, as well as the intermediate tube 3 is moved while being connected to the intermediate tube 4. Therefore, to bring the stick into the collapsed state, it takes a trouble of releasing the connected state between the tubes one by one. However, since the collapsible stick according to the present invention stops at a position suitable for folding the intermediate tubes 3, 4 only by pulling the second tube 2, handling it is very easy, which is advantageous.

Further, in the collapsible stick according to the present invention, short wires 10 are individually arranged in the connecting portions of the respective tubes. The reason for this is as follows. If one long wire is passed from the connecting portion 1b of the first tube 1 to the connecting portion 2Aa of the second tube 2, in the connection released state as shown in FIG. 6(a), it tends to get tangled with the wire 7 inside each tube. In order to avoid such a situation, short wires 10 are separately arranged at the connecting portions between the respective tubes. By doing so, without the wire 10 being tangled with the wire 7, the stick can be appropriately brought into the connected state when the unlocking button 8 is pressed. However, if it is possible to prevent the wires from being tangled with each other, a single wire 10 may be used.

In the embodiment, although the wire 10 or the retaining member 9, 11 is not arranged at the connecting portion between the intermediate tube 4 and the second tube 2, there may be arranged, similar to the other connecting portions, a wire 10 having fixing members 12, 13 attached to both ends thereof and retaining members 9, 11 through which the wire 7 and the wire 10 are inserted in the connecting portion between the intermediate tube 4 and the second tube 2.

Further, although the second tube 2 is composed of the two tubes 2A, 2B to provide the length adjusting mechanism in the embodiment, in the collapsible stick according to the present invention, providing such a length adjusting mechanism is not indispensable. However, since the appropriate length of the stick depends on the user, it is preferable to provide a length adjusting mechanism.

Although Conston springs, which are constant load springs, are used as the spring member 5 in the embodiment, a spring other than the Conston spring may be used in the collapsible stick according to the present invention. However, it is preferable to use a constant load spring because it is easy for the user to handle.

In the embodiment, the two intermediate tubes 3, 4 are arranged between the first tube 1 and the second tube 2 to form the structure composed of four tubes in total. In the collapsible stick according to the present invention, however, the number of tubular members of the stick is not limited to four, but any number may be used as long as the collapsible mechanism is provided.

Although the wire 10 and the retaining members 9, 11 are arranged in the connecting portion between the first tube 1 and the intermediate tube 3 and the connecting portion between the intermediate tube 3 and the intermediate tube 4 in the embodiment, the collapsible stick according to the present invention need not arrange these members. However, as described above, arranging these members makes handling of the stick easier in the connection released state.

1

First tube

1a

Stopper portion

1c, 3b

Contact portion

2

Second tube

3, 4

Intermediate tube

5

Spring member

6

Locking member

6a

Locking tag

7, 10

Wire

8

Unlocking button

9, 11

Retaining member

12, 13

Fixing member