JP5480673B2 - Shaft locking device - Google Patents

Description

  The present invention relates to a shaft body locking device that restricts movement in one direction of a shaft body and allows movement in the other direction, and in particular, a sleeve that engages with and disengages from the shaft body is prevented from dropping when the shaft body is pulled out. The present invention relates to a shaft body locking device.

  A device that locks (clamps or fixes) a shaft body by engaging with a shaft body such as a pipe or a rod, or sends out (push or pull out) the locked shaft body in one direction is known. For example, a collet chuck that fixes a drill blade serving as a shaft to a rotary drive shaft is widely used. In this drill chuck, the outer peripheral surface of the collet is a tapered surface, and the inner surface of the collet holder is brought into contact with the tapered surface to grip the drill blade. Here, the collet holder is coupled to the collet with a screw, and the drill blade is attached and detached by rotation of the collet holder.

  Also, in order to lay gas pipes and water pipes in the soil, the propulsion body that is the shaft body is propelled into the ground to form a horizontal hole, while this propulsion body is made of polyethylene pipe or the like at its tip. An apparatus for laying a buried pipe by connecting and retracting the buried pipe is known (Patent Documents 1 and 2). That is, a propelling body is pushed sideways from a shaft (pit) provided on the ground to reach another shaft, and one end of a polyethylene pipe is hooked on the protruding tip to pull back the propelling body.

  In this type of device, the next propulsion body is sequentially added to the tail while propelling the propelling body, but this shaft body lock is held while the rearmost propelling body is held by a shaft body locking device (also referred to as a clamp mechanism). It pushes and pulls the device.

JP-A-8-177382 JP-A-11-287088

  In Patent Document 1, the rear end of a propulsion body is held by a hydraulic clamp mechanism, and this clamp mechanism is pushed and pulled (advanced / retracted) by a hydraulic motor and a feed screw mechanism capable of forward and reverse rotation.

  The thing of patent document 2 hold | maintains a propulsion body (The punching head member 11, the extending | stretching member 18, and the drawing-in member 19) in the holder with a chuck | zipper (20) which advances / retreats by a hydraulic cylinder. Here, the holder with chuck (20) holds the propulsion body between the member receiver (21) and the eccentric cam (22) by rotating the eccentric cam (22) with the lever (24). is there. Further, when pulling back the propelling body by attaching a polyvinyl chloride pipe to the tip of the propelling body, the main body (11) including the hydraulic cylinder is rearranged in the front-rear direction.

  Since mud and sand adhere to the propulsion body and its push-pull device in the construction work of the underground pipe, it is necessary that the lock mechanism for gripping the propulsion body can be easily removed even if mud or sand is bitten. When the propulsion unit is pushed into the soil, another propulsion unit is connected to the tail in order, and when the propulsion unit is pulled out, the propulsion unit is reversely disconnected. At the time of this connection / disconnection, the locking device needs to temporarily release the propulsion unit. For this reason, it is desirable that the locking device can lock and release the propulsion body with a simple operation.

    The collet chuck for drill is troublesome to remove when mud or sand is caught in the tapered surfaces of the collet and the collet holder, and the collet holder must be rotated when the propulsion body is locked and released. For this reason, there is a problem that workability in a narrow place is poor.

  Although the thing of patent document 1 uses a hydraulic clamp mechanism, this mechanism provides the recessed part (hexagonal hole-shaped recessed part 10A) in which the rear-end part of a rear propulsion body enters, and hold | maintains in this recessed part with a hydraulic piston. Therefore, the structure is complicated and large. Moreover, since this apparatus is used in a narrow shaft, the workability in the shaft becomes very poor when the size is increased.

  The one of Patent Document 2 uses a single eccentric cam and is simple in structure and suitable for downsizing. However, there are two contact points with the propulsion body, and the gripping force by the single eccentric cam should be sufficiently large. Have difficulty. For this reason, it is conceivable that the gripping force is insufficient when a large pushing force or pulling force is applied. In particular, the propulsion body may slip under use conditions where muddy water adheres. Further, there is a problem that the wear of the receiving member that receives the eccentric cam and the propellant progresses rapidly due to repeated use over a long period of time, resulting in poor durability.

  On the other hand, conventionally, three sleeves are fitted between the taper surface formed on the body and the propulsion body, and these sleeves are pushed into the small diameter side of the taper surface to grip the propulsion body, and the sleeve is held on the taper surface. One that releases the propulsion body by pulling it out to the large diameter side can be considered. However, in this case, in order to prevent the sleeve from falling off when the propulsion body is not in the body, it is necessary to form an annular groove on the inner peripheral surface of the sleeve and load a ring-shaped spring that expands the diameter of the groove. There is. This ring-shaped spring always holds the three sleeves against the tapered surface.

  In the case of using such three sleeves, mud and sand are easily caught around the ring-shaped spring, and it is difficult to remove them. For this reason, when the propulsion body is locked and released many times, the work must be interrupted, resulting in poor work efficiency. Further, when the ring-shaped spring breaks or comes off, the sleeve falls off, and the operation interruption time becomes longer.

  The present invention has been made in view of such circumstances, has good workability in a narrow space, and can easily remove mud and sand even if it is bitten by mud and sand, has a simple structure and is suitable for downsizing and sufficient. A holding force can be generated, and even when the shaft body (propulsion body) is pulled out from the body, the sleeve can be prevented from falling off without using a ring-shaped spring for preventing the sleeve from falling off, and the durability is also excellent. An object is to provide a shaft body locking device.

According to the present invention, a first object is to provide a shaft body locking device that locks or releases the shaft body so as to allow movement of the shaft body in one direction and restrict movement in the opposite direction.
A body having a tapered surface through which the shaft passes and expands in a direction allowing movement thereof;
A plurality of guides fixed to the body at intervals in the circumferential direction around the central axis of the tapered surface and having a width in the circumferential direction on the direction side allowing movement of the shaft;
The taper surface is slidably loaded between the guides, and the outer peripheral surface thereof is guided by the taper surface by sliding the tapered surface in the diameter reducing direction, the inner peripheral surface holds the shaft body, and the taper surface is expanded. A plurality of sleeves for releasing the shaft by sliding in a radial direction ;
While the gap between the side surface of the sleeve and the side surface of the guide is formed while the shaft body is held, the side surface of the sleeve and the side surface of the guide are engaged when the shaft body is opened. Engaging means for preventing the sleeve from falling off;
Sleeve opening / closing means for locking and releasing the shaft body by moving the sleeve within a predetermined range in the sliding direction;
It is achieved by the shaft body locking device characterized by comprising.

According to the present invention, there is provided an engagement means that performs a function by the cooperation of the side surfaces of the plurality of guides fixed to the taper surface of the body and the side surfaces of the plurality of sleeves that slide. Prevent falling out with the body removed. The engaging means forms a gap between the side surface of the sleeve and the side surface of the guide while holding the shaft body, and when the shaft body is opened, the side surface of the sleeve and the guide The side surface of the sleeve engages with the sleeve to prevent the sleeve from falling off. Here, the sliding range (movable range) of the sleeve is regulated by the sleeve opening / closing means, and the sleeve is prevented from falling off the guide by the engaging means.

  For this reason, the shaft body can be locked and released by moving the sleeve in the sliding direction by the sleeve opening / closing means, so that it is not necessary to rotate the collet holder like the collet chuck, and the workability in a narrow place is good. By repeatedly sliding the sleeve back and forth by the sleeve opening / closing means with the shaft body removed, mud and sand that have entered between the sleeve and the tapered surface can be easily removed.

  Since the sleeve is slid back and forth by the sleeve opening / closing means, the structure is simpler than that using a hydraulic chuck (see Patent Document 1) and is suitable for downsizing. For this reason, workability in a narrow place (such as in a shaft) is good.

  Since the number of sleeves for gripping the shaft body can be increased to three or more, the shaft body can be gripped at three or more locations in the circumferential direction. Therefore, a strong holding force can be generated, and the sleeve is held at three or more positions, so that wear of the sleeve is reduced and durability is excellent. Further, when the shaft body is pulled out, the sleeve is prevented from falling off by the engaging means formed with the side surface of the guide. This eliminates the need for a ring-shaped spring for preventing the sleeve from falling off and simplifies the structure.

The front view of one Example of this invention, and the single figure of a guide and a sleeve II-II line sectional view in FIG. Front view of the guide IV-IV sectional view in FIG. Side sectional view showing the locked state VI-VI line sectional view in FIG. Side sectional view showing the open state VIII-VIII sectional view in FIG. The front view which shows the sleeve opening-closing means of a present Example Left side view in FIG.

  The present invention is suitable for a pushing / pulling device for a propulsion body used for laying an underground pipe, but the present invention is not limited to this and can be applied to one that locks or unlocks a pipe or a rod-like member. . For example, there are various uses such as setting the shower holding position in the bathroom to a desired height above and below, or setting the spotlight to a free height of a pipe fixed to the wall, and the present invention includes these To do.

It said engaging means, on a plane the central axis of the tapered surface is perpendicular, the that imaginary lines intersect obtained by extending the both side surfaces of each sleeve and eccentric to the sleeve side from the center axis of the tapered surface In this case, the side surface of the sleeve may be substantially parallel to the side surface of the opposing guide . Therefore, the gap (circumferential gap) between the side surfaces of the pair of guides sandwiching the sleeve is narrow on the central axis side. For this reason, it is prevented that the sleeve falls off inward (center line side). In this case, the side surfaces of the sleeve and the guide are flat or close to each other, so that it is easy to remove even if mud or sand is caught in the gap.

  It is sufficient that one or both of the sleeve and the side surface of the guide pass near the eccentric position. The meaning of “substantially parallel” is also clear from the object and effect of the present invention that prevents the sleeve from falling off between the guides when there is no shaft.

  Instead of forming the side surfaces of the sleeve and the guide with a plane having a predetermined angle as described above, the engaging means is a key groove provided on one side surface and a key engaged with this provided on the other side surface. It may be configured with. In this case, the key groove and the key are inclined so that the sleeve is abutted (or lowered) substantially along the tapered surface as the sleeve slides.

  When the sleeve moves in a direction allowing the movement of the shaft body (a direction in which the shaft body is released), the engagement means raises the sleeve to the outer peripheral side with a rising angle that does not exceed the taper angle of the tapered surface. Is required (Claim 3). This is because the sleeve is not locked between the tapered surface and the engaging means.

The engaging means forms a gap between the side surface of the sleeve and the side surface of the guide in a state where the sleeve holds the shaft body, but this gap is sufficient, and the sleeve locks the shaft body by this gap. The taper surface can be reliably contacted and the sleeve can be reliably pressed against the shaft body.

Three guides having the same shape and three sleeves having the same shape are provided, and these guides and sleeves are alternately arranged in the circumferential direction, and both side surfaces of each sleeve are opposed to the side surfaces of two different guides. Accordingly, the shaft body can be gripped by the three sleeves, and the gripping force can be sufficiently increased (claim 4 ). Of course, the number of guides and sleeves is not limited to this.

The sleeve opening / closing means includes a sleeve opening / closing key held on the body so as to be movable back and forth in a direction parallel to the central axis of the tapered surface, and a push member fixed to the sleeve opening / closing key and engaged with each sleeve to move the sleeve forward / backward. (Claim 5 ). In this case, the sleeve opening / closing key can be moved forward and backward by a handle lever that is swingably held on the body by a swing shaft orthogonal to the central axis of the tapered surface .

The push member is fixed to both ends of the sleeve opening / closing key and is attached to a pair of ring members opposed to both ends of the body, and the push member attached to one of the ring members is an adjustment bolt capable of adjusting a distance from the sleeve. (Claim 7 ). The position where the sleeve locks the shaft body can be accurately determined by the adjusting bolt.

  9 and 10 show a propulsion body locking device 10 for laying underground pipes to which the present invention is applied. The lock device 10 is attached to a pedestal (not shown) and is moved forward and backward by a hydraulic cylinder. The pedestal is fixed in the shaft, and the locking device 10 pushes out the propulsion body 12 that is a shaft body in the right direction (arrow A direction) in FIG. 10 by a hydraulic cylinder. The propulsion body 12 successively adds propulsion bodies that are sufficiently shorter than the diameter of the shaft. At that time, the locking device 10 releases the propulsion body 12 and moves backward to the rear side, locks the propulsion body 12 again, moves forward, and pushes the propulsion body 12 into the ground. When the propulsion body 12 is pulled back, the locking device 10 is reversed left and right to grip the propulsion body 12 and pulled back by the hydraulic cylinder.

  9 and 10, reference numeral 14 denotes a body, and the body 14 is formed with a tapered surface 16 whose diameter increases in the direction of arrow A (the pushing direction of the propelling body 12). The gradient of the tapered surface 16 is set to 9 °, for example (see FIG. 2). A sleeve 18 described later is loaded between the tapered surface 16 and the propulsion body 12. The sleeve 18 is slid left and right in FIG.

  The sleeve opening / closing means 20 includes a handle lever 26 that is fixed to the body 14 by a swing shaft 24 that is orthogonal to the central axis 22 of the tapered surface 16, and whose lower portion branches to both sides of the body 14, and a central axis 22 on the side surface of the body 14. A pair of left and right sleeve opening / closing keys 28 held so as to be movable back and forth in a parallel direction, a pair of ring members 30, 32 fixed to the front and rear ends of these sleeve opening / closing keys 28, and attached to both ring members 30, 32, respectively. And a plurality of push members 34 and 36 engaged with both ends of the sleeve 18. One push member 34 is an adjustment bolt capable of adjusting the distance from the sleeve 18.

  A horizontal rotating plate 38 is fixed to the lower surface of the body 14, and a rotating shaft pin 40 is fixed to the center of the rotating plate 38 (on the vertical center line of the body 14) so as to protrude downward. . The rotary shaft pin 40 is rotatably supported by a slide member (not shown) that slides by a hydraulic piston. An appropriate number (for example, two) of positioning pins 42, 42 are mounted on the rotating plate 38 at symmetrical positions with the rotating shaft pin 40 interposed therebetween. When the positioning pin 42 is pulled up, the rotating plate 38 can be rotated. The positions of 9 and 10 can be reversed left and right. That is, the position can be switched between a position where the propelling body 12 is pushed in the direction of arrow A and a position where the propelling body 12 is pulled out by being reversed in the direction of the opposite arrow A. The rotating plate 38 is preferably fixed by adding other appropriate fixing means.

  Next, the locking device of the present invention will be described with reference to FIGS. The front view of FIG. 1 is a view of the tapered surface 16 formed on the body 14 as seen from the large diameter side. That is, it is a view seen from the right side in FIG. The single view of the guide 50 and the sleeve 18 is a view as seen from the central axis 22 side of the tapered surface 16. The guide 50 and the sleeve 18 are curved in an arc shape so as to be in close contact with the inner surface of the tapered surface 16 as is apparent from the front view. The guide 50 is substantially fan-shaped with the width gradually decreasing toward the rear surface.

  Three guides 50 are fixed to the tapered surface 16 at equal intervals in the circumferential direction. The guide 50 is fixed to the tapered surface 16 with screws with an end face having a wide width (width in the circumferential direction) written in FIG. The sleeve 18 is slightly narrower in width than the end surface written as “rear surface” opposite to the end surface written as “front”. The three sleeves 18 are loaded between the guides 50, respectively.

Here, as shown in the front view of FIG. 1, the left and right side surfaces 18A of the sleeve 18 are larger than the central axis 22 of the tapered surface 16 when viewed on a plane in which the central axis 22 is vertical (on the paper surface of FIG. 1). located on the radius of a circle around the (a position close to the sleeve 18) around a position displaced to the side of the sleeve 18. That small circle 52 centered on the central axis 22 is located on the radius of the circle around the intersection point 54 that intersects the line passing through the center of the center line 22 and the sleeve 18. Further, the angle between the side surfaces 18A and 18A toward the intersection 54 at the front end face is 60 °.

  The side surfaces 50A and 50A of the guide 50 are parallel to the side surfaces 18A and 18A of the sleeve 18 and form engagement means. Further, the side surfaces 50A and 50A form a slight gap G between the side surface 50A and the side surface 18A of the sleeve 18 in a state where the sleeve 18 holds the propulsion body 12 (see the front view of FIG. 1). This gap G is for ensuring that the sleeve 18 is clamped between the propulsion body 12 and the tapered surface 16. If the gap G is too large, the sleeve 18 falls out between the guides 50 when the propulsion body 18 is not present. In the embodiment, the gap G is set to 0.6 mm for the propulsion body 18 having a diameter of 36 mm. The radius of the small circle 52 is 4 millimeters.

  The operation of this embodiment will be described with reference to FIGS. When the handle lever 26 shown in FIGS. 9 and 10 is tilted in the locking direction, the sleeve 18 is pushed in the direction of arrow B shown in FIG. The sleeve 18 is pressed against the propulsion body 12 by the tapered surface 16 and can hold (lock) the propulsion body 12. At this time, a slight gap G is formed between the side surface 18A of the sleeve 18 and the side surface 50A of the guide 50 as shown in FIG.

  If the handle lever 26 is swung to the release side in the opposite direction, the sleeve 18 is pushed in the direction of arrow C as shown in FIG. At this time, the side surface 18A of the sleeve 18 reduces the gap between the side surface 50A of the guide 50, and when the gap is eliminated, the sleeve and the side surface of the guide 50 come into contact with each other, and the sleeve 18 is guided to the side surface of the guide 50. And slide along the tapered surface 16. That is, the sleeve 18 competes toward the tapered surface 16. FIG. 8 shows this state. An arrow D in FIG. 7 indicates the moving direction of the sleeve 18 at this time.

10 Locking device 12 Propulsion body (shaft body)
14 Body 16 Tapered surface 18 Sleeve 20 Sleeve opening / closing means 22 Center axis of taper surface 24 Oscillating shaft 26 Handle lever 28 Sleeve opening / closing key 30, 32 Ring member 34, 36 Push member 50 Guide G Gap

Claims (7)

In the shaft body locking device that locks or releases the shaft body so as to allow movement of the shaft body in one direction and restrict movement in the opposite direction,
A body having a tapered surface through which the shaft passes and expands in a direction allowing movement thereof;
A plurality of guides fixed to the body at intervals in the circumferential direction around the central axis of the tapered surface and having a width in the circumferential direction on the direction side allowing movement of the shaft;
The taper surface is slidably loaded between the guides, and the outer peripheral surface thereof is guided by the taper surface by sliding the tapered surface in the diameter reducing direction, the inner peripheral surface holds the shaft body, and the taper surface is expanded. A plurality of sleeves for releasing the shaft by sliding in a radial direction ;
While the gap between the side surface of the sleeve and the side surface of the guide is formed while the shaft body is held, the side surface of the sleeve and the side surface of the guide are engaged when the shaft body is opened. Engaging means for preventing the sleeve from falling off;
Sleeve opening / closing means for locking and releasing the shaft body by moving the sleeve within a predetermined range in the sliding direction;
A shaft body locking device comprising: It said engaging means, on a plane the central axis of the tapered surface is perpendicular, the that imaginary lines intersect obtained by extending the both side surfaces of each sleeve and eccentric to the sleeve side from the center axis of the tapered surface The shaft body locking device according to claim 1 , wherein a side surface of the sleeve is substantially parallel to a side surface of the opposing guide . The said engaging means auctions the said sleeve to the outer peripheral side with a hoisting angle which does not exceed the taper angle of the said taper surface, when the said sleeve moves to the direction which accept | permits the movement of the said shaft. Shaft body locking device. The three guides having the same shape and the three sleeves having the same shape, the guides and the sleeves are alternately arranged in the circumferential direction, and the two side surfaces of the sleeves are different from each other. The shaft body locking device according to any one of claims 1 to 3, which faces the side surface. The sleeve opening / closing means includes a sleeve opening / closing key held on the body so as to be movable back and forth in a direction parallel to a central axis of the tapered surface, and a sleeve opening / closing key fixed to the sleeve opening / closing key and engaged with each of the sleeves. The shaft body locking device according to claim 1, further comprising a push member that moves forward and backward . 6. The sleeve opening / closing means according to claim 5, further comprising a handle lever that is swingably held on the body by a swing shaft orthogonal to a central axis of the tapered surface, and the handle lever moves the sleeve open / close key forward and backward. Shaft body locking device to be moved. 6. The push member according to claim 5, wherein the push member is attached to a pair of ring members fixed to both ends of the sleeve opening / closing key and opposed to both ends of the body, and the push member attached to one of the ring members is connected to the sleeve. Shaft body locking device that is an adjustment bolt with adjustable spacing .

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