JPS6234940Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is capable of gripping the object to be lifted using a clamping means having a relatively smooth gripping surface during lifting work in a steady state. Avoid leaving a scar, but allow an eccentric safety cam with a relatively sharp textured surface to protrude and cut into the surface of the article as it attempts to slide out of the clamp, leaving a scar. , relates to improvements in so-called non-hazardous clamps that prevent slip-and-fall accidents.

Conventionally, a clamp is known in which a clamping means and a shackle are mechanically coupled to provide a clamping force proportional to the weight of the article to be lifted (for example, see Japanese Patent Laid-Open No. 42557/1983). In addition, a non-damaging clamp in which a safety cam is provided on a clamp having such a configuration is also known (for example, Japanese Patent Application Laid-Open No. 53-143858).
issue).

However, in these known techniques, the safety cam is often provided on the leg opposite to the leg on which the tightening means that interlocks with the shaft is provided, and the pivot portion of the safety cam itself is must be installed, requiring extra parts.

Furthermore, when a clamping force is applied to the clamping means in conjunction with the shaft during lifting, sufficient gripping force cannot be obtained until the object is lifted and the load is completely lost by the clamp. It is also described in the above-mentioned document to pre-tighten the article in the slot prior to lifting or to provide means for releasing the article from the clamp after unloading. However, in the conventional means, the tightening means is pushed out into the slot by a screw,
Alternatively, since it was designed to be retracted from the slot, the operation was time-consuming and workability was extremely poor.

Furthermore, as mentioned above, the structure becomes complex because the interlocking mechanism between the shaft and the tightening means, the safety cam means, the pre-tightening means before lifting, etc. are incorporated into the limited space of the clamp body, and the number of parts increases. Therefore, improvements in these points were desired.

The present invention aims to provide an atraumatic clamp with improved workability.

In the present invention, the tightening means is provided with a relatively smooth gripping surface that is linked to the shaft and eccentrically supported on one of a pair of legs forming a slot in the clamp body. A cam is used to move between a rest position in which the tightening cam is restrained in a position retracted from the slot and an active position in which the tightening cam is spring biased to extend into the slot. The above-mentioned operability is improved by providing lockable latching means.

A further object of the invention is to provide a safety cam with a reduced number of parts that presses the safety cam against the article with a substantially constant biasing force, regardless of the thickness of the article to be lifted. This is accomplished by coaxially pivoting the tightening cam and the safety cam, spring-biasing the safety cam with respect to the tightening cam, and retracting the gripping surface of the tightening cam by the desired width from the locking surface of the safety cam. There is.

Preferred embodiments and some modifications of the present invention will be described in more detail below with reference to the drawings.

FIG. 1 is a front view showing a preferred embodiment of the present invention, and FIG. 2 is a perspective view of the embodiment shown in FIG. 1 and an exploded state of some of the parts assembled therein. FIG.

In this embodiment, the clamp body 10 includes a pair of side plates 11, 11'. Side plate 11
has a pair of legs 11a, 11b forming a slot S for receiving an article to be lifted, and a base 11c connecting them. In FIG. 2, the side plate 11 is shown as having a reinforcing portion 13 with increased thickness along the slot S, but this is omitted in FIG. 1 to simplify the drawing. The side plates 11 and 11' have substantially the same shape. These pair of side plates are separated from each other via a plurality of spacers 12, and a plurality of fixing means 1
4,14'. In this embodiment, the fastening means 14 are shown as fastening means 14' consisting of a bolt nut 14, a pin and a locking pin. Various parts described below are housed between the pair of side plates 11 and 11'. However, the above-described configuration is merely an example, and the essential requirement of the clamp body 10 is that it has a slot S and can support related parts.

In this embodiment, the shackle 20 includes a first member 21 whose one end is pivotally connected between the pair of side plates 11 and 11' by a bolt and nut 14, and whose free end is pivotally connected by a pin 22. The second member 23 is shown as having a second member 23. Second member 23
has a protrusion 23a on one side between an end having an eye hole I for coupling to a wire of a crane or the like and an end pivotally attached to the first member 21, and a recess 23b on the opposite side. has. These protrusions 23a and recesses 2
3b means that even when the eye hole I is pulled in the left and right direction in FIG. 1 by coming into contact with the spacer 12 provided close to both sides of the first member 23, It is designed to provide a tightening force proportional to the tensile force. That is, in this embodiment, not only vertical hanging but also horizontal hanging is possible. The features of the shackle described above are not essential; the essential requirement is that the shackle be pivotally connected to the clamp body so that when a tensile force is applied to the shackle, the tightening means described below are interlocked to tighten the article inserted into the slot. That's true.

A clamping means 30 is provided on one leg of the clamp body formed by the leg 11a of the side plate 11 and the corresponding leg of the side plate 11'. The fastening means 30 is a coupling means 1 consisting of a pin and a locking pin.
Tightening cam 31 pivotally mounted eccentrically by 4'
and a link arm 33 whose one end is pivotally connected to the tightening cam 31 by a shaft pin 32.
The clamping cam 31 has a relatively smooth gripping surface 31a that is eccentric with respect to the pivot shaft 14'. In this embodiment, a tightening cam 3 having the same shape as the tightening cam 31 is used.
1' is shown (FIG. 2) as coaxially pivoted across the safety cams described below, but it is sufficient to have at least one tightening cam. One end of the link arm 33 is pivotally connected to the tightening cams 31, 31' by an axle pin 32, and the other end is connected to the first member 21 of the shaft 20 by an axle pin 34.
It is pivoted by. Therefore, the shackle 20
When a tensile force is applied to the clamping means, the clamping means rotates the gripping surface 31a clockwise in FIG. (side plate 1)
1 and the corresponding leg portions of the side plate 11'). In this embodiment, this opposite leg is provided with receiving means 40. The receiving means 40 includes a gripping member 41 which is pivotally connected to the opposite leg by coupling means 14'.
The gripping member 41 has a relatively smooth gripping surface 41.
It has a. Since both the gripping surface 31a of the clamping means 30 and the gripping surface 41a of the receiving means 40 have relatively smooth surfaces, deep scratches can be prevented when an article is clamped between them. Providing the gripping member 41 on the opposing leg is desirable in that the gripping surface 41a follows the movement of the tightening cam, but it is not essential, and it is only essential that the opposing leg be provided with a relatively smooth gripping surface 41a. It is. In the embodiment shown in FIG. 2, the gripping surface 41a of the gripping member 41 has the aforementioned tightening cam 3.
1 and 31', a narrow and shallow groove 41 extending laterally in FIG.
b is provided to prevent slippage, and a relatively wide groove 41 extending longitudinally in FIG.
c is provided.

The safety cam means 50 includes a safety cam 51 pivotally mounted coaxially with the tightening cam 31 (coupling means 14'), a spring means 52 for spring biasing the safety cam 51 toward the slot S side with respect to the tightening cam, and the safety cam 51 and the tightening cam. Means 5 for allowing relative movement with 31 within a limited range
3. The safety cam 51 has a locking surface 51a that is eccentric with respect to the pivot shaft (coupling means 14') and has relatively sharp unevenness, and the gripping surface 31a of the tightening cam is attached to the locking surface 51 by a desired width.
Their distance from the center of rotation increases as they retreat from a. The spring means 52 is shown as a coil spring in the illustrated embodiment, and one end thereof is engaged with a spring engagement means 51b protruding from the safety cam 51, and the other end thereof is engaged with a spring engagement means 51b protruding from the tightening cam 31. It is shown as being locked to the stop means 31b. However, it is clear that other spring means and spring locking means may be used.
This prevents the locking surface 51a of the safety cam 51 from protruding more than necessary from the gripping surface of the tightening cam 31, and also prevents the locking surface 51a of the safety cam 51 from protruding beyond the gripping surface of the tightening cam 31.
In order to allow the clamping cam 31 to move backward against the biasing force of the spring means 52 until it is aligned with the gripping surface 31a.
A protrusion 51c extending toward the other (the tightening cam 31 in the illustrated embodiment) is provided on one of the axially overlapping portions of the safety cam 51 (the safety cam 51 in the illustrated embodiment), and the other (the tightening cam 31 in the illustrated embodiment). In the illustrated embodiment, the tightening cam 31) has a hole 31c with a play that allows the protrusion 51c to move within a limited range.
is provided. The vertical groove 41c in the gripping surface 41a is formed in the locking surface 4 when the safety cam is activated.
The elasticity of the article being suspended relative to 1a ensures a positive locking action.

Latching means 60 is shown in this embodiment as including a latch lever 61, a crank 62, a tension coil spring 63, and a cantilever rod 64, restricting means 65. The latch lever 61 is the side plate 1
1', and is rotatably supported by a side portion 62a of a crank 62 inserted into a pivot hole provided in the side plate 11' from inside the side plate 11'. A rectangular projection 62 is provided at the tip of the shaft portion 62a.
b is provided, which fits into the square hole of the latch lever so that the latch lever 61 and crank 62 rotate together. crank 62
The arm 62c has an arm 62c extending perpendicularly to the axial direction of the shaft portion 62a, and a protrusion that is not aligned with the shaft portion 62a is erected on a part of the arm 62c to form a spring locking means 62d. That is, this spring locking means 62d is
Rotates together with the latch lever. Tension coil spring 6
One end of 3 is coupled to a spring locking means 62d. In the illustrated embodiment, cantilever rod 64 is also shown as being pivotally connected to spring locking means 62d.

The other end of the coil spring 63 has a pin inserted into a pin hole provided in a protrusion provided at the lower end of a link arm linking the tightening cam 31 of the tightening means 30 and the first member 21 of the shackle means 20. It is locked by a spring locking means 33a formed as .

In order to explain the operation of the latching means 60, the side plate 11 is removed and the coil spring 63 is shown in FIG.
A portion of a front view in section with a portion cut away is shown. In FIG. 3, the latching means in the rest position are shown in solid lines, and the active position is shown in dash-dotted lines. In the rest position of the latch means 60, the spring locking means 62d and 33a are both on one side of the pivoting portion of the latch lever 61 and are closest to each other, and the spring locking means 62d is the spring locking means 33a. 33a and the pivot portion 62a (on the right side in FIG. 3). In this position, the free end of the cantilever rod 64 is located adjacent to the spring locking means 33a of the link arm 33. The restricting means 65 is formed as a cylindrical stopper projecting from the inner surface of the side plate 11', and prevents the crank 62 from rotating further counterclockwise from the position shown in FIG. 3 in the rest position. ing. Therefore, when the latching means is in the rest position, when a tension force is applied to the shackle means 20, the link arm 33 with respect to the clamp body
cannot be pulled upward, and the gripping surface 31a of the tightening cam is locked in a position retracted from the slot.

When the latch lever 61 is rotated clockwise from the position shown in FIG. Ru. When pivoting from the rest position to the active position, the spring locking means 6
2d is a spring locking means 33a with respect to the pivot portion 62c.
passing a point opposite and in line with the coil spring 63 , when the coil spring 63 is under maximum tension, and when rotating further clockwise from that point towards the active position, the coil spring 63 shrinks slightly. Since the crank 62 is stopped by the limiting means, the coil spring 63 pulls the spring locking means 33a of the link arm upward, and the tightening cam 31
can be rotated clockwise to pre-tighten the article in the slot between the gripping surfaces 41a and 31a.

It is clear that the procedure described above can be reversed when releasing the article from the clamp. As described above, according to the present invention, the pre-tightening and releasing operations before and after lifting can be performed with a single touch, so that work efficiency is significantly improved.

Furthermore, by arranging the safety cam 51 and the tightening cam 31 coaxially, the structure of the clamp is simplified, the number of parts is reduced, the dimensions of the clamp itself are reduced, and the weight of the clamp itself is also reduced. I can do it.

In the embodiment described above, the cantilevered rod may be pivotally attached to the pin of the spring locking means 33a. Further, it is not essential to provide the spring locking means 33a on the link arm 33, and when the tightening cam 31 rotates from the retracted position to the maximum extended position, the latch means 6
It can be provided at any position on the tightening means 30 that gradually approaches the pivot portion 62a of 0. Furthermore, the limiting means 65 need not be a single stopper, but may be provided respectively for the active position and the rest position. Furthermore, the latch lever can optionally be arranged between the side plates 11, 11', in which case the crank 62 can be omitted and the spring locking means can be provided directly on the latch lever. I can do it.

Although the present invention has been described above in detail based on the embodiments of the present invention, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the technical idea of the present invention. It is.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the clamp of the present invention, Fig. 2 is a perspective view of the clamp of the above embodiment and parts separated therefrom, and Fig. 3 is a latch means of the above embodiment. It is a front view with a part removed showing a part. Explanation of symbols, 10... Clamp body, 11, 1
1'...Side plate, 12, 12'...Spacer, 11
a, 11b...leg, 11c...base, 13...
Reinforcement part, 14, 14'... Fixing means, 20... Shackle, 21... First member of the shackle, 22
... Pin, 23 ... Second member of the shaft, 30
...Tightening means, 31...Tightening cam, 31a...
...Smooth grasping surface, 31c...hole, 40...receiving means, 41...gripping member, 41a...smooth grasping surface, 50...safety cam means, 51...safety cam, 51a...locking surface , 51c...protrusion, 60...
... Latch means, 61 ... Latch lever, 62 ...
Crank, 62d... Spring locking means 63... Tension coil spring, 64... Cantilever rod, 65... Limiting means.

Claims (1)

[Claims for Utility Model Registration] (1) A slot for receiving an article to be hoisted by a pair of legs that are spaced apart from each other and a base that connects one end of each leg. a clamp body, a shackle pivotally connected to the clamp body, a tightening cam pivotally connected to one of the pair of legs and having a relatively smooth eccentric surface as a gripping surface; a tightening means having a link arm interlocked with the shaft; and a tightening means disposed on the other leg;
a receiving means having a relatively smooth gripping surface and gripping the article in cooperation with the tightening means; and an eccentric having relatively sharp unevenness, the receiving means being pivotally attached to one of the pair of legs. a safety cam having a surface as a locking surface; a safety cam means having a spring biasing the locking surface to project into the slot; and a safety cam means having a spring biasing the locking surface to project into the slot; In a type of clamp having latching means lockable in an active position that provides a biasing force and a rest position that does not provide said biasing force, the clamping cam and the safety cam are one of a pair of legs. are coaxially adjacent and pivotally connected, one of their adjacent surfaces is provided with a protrusion extending toward the other, and the other side has a play that allows said protrusion to move within a limited range. a hole is provided therein, and a spring biasing means is provided between the tightening cam and the safety cam so that the locking surface of the safety cam projects further toward the slot than the gripping surface of the tightening cam. and an intact clamp. (2) The latch means includes a latch lever rotatably pivoted to the clamp body, a spring locking means rotating together with the latch lever, a tension coil spring having one end locked to the spring locking means, and a tension coil spring having one end locked to the spring locking means. a cantilever rod inserted into a coil spring;
limiting means for limiting rotation of the latch lever between an active position and a rest position; the other end of the coil spring is configured to move the latch lever from a retracted position in which the gripping surface of the tightening cam is completely retracted from the slot; When the latch lever is rotated forward in a direction in which the latch lever is pushed out, the latch lever is locked by a spring locking means provided at an arbitrary position on the tightening means that moves toward the pivot shaft of the latch lever, and rotates together with the latch lever. The spring locking means is configured such that when the tightening cam is in the retracted position,
The cantilever rod is arranged between the spring locking means on the tightening means and the pivot shaft of the latch lever, and the cantilever rod is pivotally connected to one of the two spring locking means. and the free end of the rod has a length such that, when the clamping cam is in the retracted position, the free end of the rod abuts the other spring locking means, in which position the limiting means prevents the latch lever from moving in one direction. Rotation is prevented to provide the latch means with a rest position, and when said latch lever is rotated in the opposite direction from the rest position, the spring locking means rotating with the latch lever is gradually moved away from the other spring locking means and the latch lever is rotated in the opposite direction from the rest position. At a point on the opposite side with respect to the pivot axis, the tension spring is stretched to its maximum extent, and when it rotates further in the opposite direction, it is again prevented from further rotation in the opposite direction by the restricting means, and in that position. the free end of said cantilever rod is spaced from said other spring locking means;
2. An intact clamp according to claim 1, characterized in that the clamping cam is thereby rotated forward by the tensioning spring and held in an active state for interlocking with the shaft.