JP4434765B2 - Fork backlash prevention device - Google Patents

Description

  The present invention relates to an improvement in a fork back-preventing device that is applied to a cargo handling vehicle such as a forklift to prevent fork backlash.

Conventionally, for example, the following devices are known as this type of fork backlash prevention device.
(1) The fork is provided with an elastic member or a sliding member to prevent backlash between the fork and the finger bar (see Patent Documents 1 to 7).
(2) A bolt member is provided on the lower hook to prevent backlash between the lower hook and the finger bar, thereby preventing backlash of the fork (see Patent Documents 8 to 11).

JP 59-17499 Japanese Utility Model Publication No. 60-85599 Japanese Utility Model Publication No. 62-100992 Japanese Patent Laid-Open No. 4-182300 Utility Model Registration No. 2523333 Utility Model Registration No. 2575191 JP 2002-265193 A Japanese Utility Model Publication No. 6-15978 JP 7-69596 A Japanese Patent No. 3232838 JP-A-11-171490

However, in the former, since the backlash between the fork and the finger bar is always prevented by the elastic member and the sliding member provided on the fork, the left and right forks are moved along the finger bar to adjust the interval. In doing so, the sliding resistance increased and this was difficult to do.
On the other hand, in the latter, the fork can be moved by loosening the bolt member, but the bolt member is provided on the back surface of the lower hook, so that it is difficult to perform the screwing operation. As a result, this could not be easily done when moving the fork. However, since the lower hook had to be formed with a screw hole corresponding to the bolt member, there was a problem that the strength of the lower hook was lowered.

  The present invention was devised in view of the above-mentioned problems, and was devised to solve this problem. The problem is that when the fork is moved, this can be easily performed, and the backlash of the fork is prevented. However, it is still another object of the present invention to provide a backlash prevention device for a fork that does not reduce the strength of the fork, the lower hook, or the like.

  The ratchet prevention device for a fork of the present invention basically includes a fork support that can be raised and lowered, a fork that is suspended laterally on the fork support, a fork support that is provided on the fork support, and the fork. It is characterized by the fact that it is composed of wedge means that can be inserted and opened between the two.

When the wedge means is inserted between the fork support and the fork, the fork does not rattle against the fork support.
If the wedge means is released from between the fork support body and the fork, the fork may be rattled against the fork support body, but the sliding resistance of the fork with respect to the fork support body is reduced accordingly. It can be moved easily and the distance between the forks can be adjusted easily.
Since the wedge means is provided on the fork support body, it is not necessary to process the fork and the lower hook, there is no possibility that the strength is lowered, and a conventional one can be used as it is.

  The wedge means includes an inclined surface provided on the fork support body to form a wedge-shaped space with the back surface of the fork, and both ends supported by the fork support body and a middle portion between the back surface of the fork and the inclined surface. Is inserted into the upper chord bent state and both ends are supported by the fork support, and the middle is elastically deformed to the lower chord bent state opened from between the back surface and the inclined surface of the fork. It is preferable to provide an arcuate wedge body. In this way, since the inclined surface is provided, a large wedge effect can be exhibited. Since the wedge body is provided on the fork support, there is no risk of losing it. Since the wedge body is held in the insertion position and the open position by its own elasticity, it is not necessary to provide a separate holding mechanism, and the structure can be simplified and the cost can be reduced. Since the wedge body is held in the open position, it is not necessary for the operator to hold the wedge body in the open position when moving the fork.

  The wedge means is provided on the fork support and forms an inclined surface that forms a wedge-shaped space with the back surface of the fork, and is raised with a fitting position that is lowered and fitted between the back surface and the inclined surface of the fork. A wedge body that can take an open position that is opened from between the back surface and the inclined surface of the fork, and a guide mechanism that is provided between the fork support body and the wedge body and guides the wedge body so that it can be raised and lowered. It is preferable. In this way, since the inclined surface is provided, a large wedge effect can be exhibited. Since the wedge body is provided on the fork support, there is no risk of losing it.

  The guide mechanism preferably includes a plurality of links and a connecting pin that connects the links in a refractive manner. In this way, the structure of the guide mechanism can be simplified and the cost can be reduced.

  The guide mechanism preferably includes an elongated hole and a pin engaged with the elongated hole. In this way, the structure of the guide mechanism can be simplified and the cost can be reduced.

  The elongated hole preferably includes a vertical hole that allows the wedge body to move up and down, and a horizontal hole that is continuous to the wedge body to keep the wedge body in an open position. In this way, since the wedge body is held in the open position, it is not necessary for the operator to hold the wedge body in the open position when the fork is moved.

According to the present invention, the following excellent effects can be achieved.
(1) Consists of a fork support, a fork, and a wedge means, and in particular, a wedge means that can be fitted and opened between the fork support and the fork is provided on the fork support. Can do this easily and still prevent backlash on the fork.
(2) Since the fork support body is provided with wedge means that can be inserted into and removed from the gap between the fork support body and the fork, the strength of the fork, lower hook, etc. is not reduced. As a result, the conventional fork can be used as it is.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a rear view showing a fitting state of a fork rattle prevention device according to a first example of the present invention. FIG. 2 is a side view of FIG. FIG. 3 is a view similar to FIG. 1 showing the open state. FIG. 4 is a side view of FIG.

  The fork rattle prevention device 1 is composed mainly of a fork support 2, a fork 3, and wedge means 4, and is applied to a cargo handling vehicle such as a forklift.

  The fork support 2 can be moved up and down. In this example, the left and right lift brackets 5, upper and lower finger bars 6, 7 provided on the front side thereof, and both finger bars 6 on the front side of the lift bracket 5 are provided. 7, left and right center plates 8 and left and right side plates 9 provided between both ends of both finger bars 6 and 7 are not shown. It is provided so as to be movable up and down along a mast provided on the front side of the vehicle body so as to tilt forward and backward.

The lift bracket 5 has a plate shape.
The upper finger bar 6 has a horizontally long prismatic shape, is erected on the upper front surface of the lift brackets 5, and has an upward protrusion 10 formed on the upper part. The protrusions 10 of the upper finger bar 6 are formed with engagement notches 11 for engaging positioning stopper pins (not shown) at predetermined intervals, and these restrict the movement of the fork 3 in the left-right direction. As a result, the distance between the forks 3 can be adjusted.
The lower finger bar 7 has a horizontally long prismatic shape, is erected on the lower front surface of the lift brackets 5, has a downward protrusion 12 formed at the lower portion, and has a fork 3 at the lower center. A notch 13 for inserting / removing is formed.

The fork 3 is suspended from the fork support 2 so as to be laterally movable. In this example, the fork 3 is a pair of left and right, and has a substantially L shape including a vertical piece 14 and a horizontal piece 15, respectively. An upper hook 16 is attached to the upper back surface of the piece 14 so as to be in an inverted substantially L shape and is engaged with the protrusion 10 of the upper finger bar 6. A lower hook 17 that is engaged with the protrusion 12 of the lower finger bar 7 is attached.
Although not shown, the upper hook 16 is provided with a positioning stopper pin that is biased downward by a spring.

The wedge means 4 is provided on the fork support 2 and can be fitted / released between the fork support 2 and the fork 3. In this example, the wedge means 4 is provided on the fork support 2 and the rear surface of the fork 3. An inclined surface 19 that forms a wedge-shaped space between the fork 18 and both ends are supported by the fork support 2, and the middle is inserted between the back surface 18 and the inclined surface 19 of the fork 3 so that the upper chord is bent. An arcuate shape that can be elastically deformed into a fitting position and an open position where both ends are supported by the fork support 2 and the middle is opened from between the back surface 18 and the inclined surface 19 of the fork 3 and becomes a lower chord curve state. And a wedge body 20.
A long groove 21 is formed in the lower inner surface of each side plate 9 of the fork support 2, and is formed to be inclined forward so that the upper side is the front and the lower side is the rear.
The inclined surface 19 is formed by a front surface of an inclined plate 22 attached to the upper portion of the lower finger bar 7 in the vicinity of the inside of the center plate 8 by being inclined backward by a predetermined angle θ.
The wedge body 20 is made of a so-called substantially wedge-shaped, straight wedge having a thin trapezoidal shape as the cross section goes downward, and is bent into an arcuate shape by bending it into a long groove 21 at both ends. In other words, a so-called toggle mechanism that can take the upper and lower folds is used.

Next, the operation will be described based on such a configuration.
As shown in FIGS. 1 and 2, when the wedge body 20 of the wedge means 4 is elastically deformed into the upper chord bent state, both ends of the wedge body 20 are positioned above the long groove 21 as shown by the solid line in FIG. The middle part is firmly inserted between the back surface 18 of the fork 3 and the inclined surface 19 of the inclined plate 22 to be in the insertion position. Then, the backlash of the fork 3 with respect to the fork support 2 is prevented.

  On the contrary, as shown in FIGS. 4 and 5, when the wedge body 20 of the wedge means 4 is elastically deformed into the lower chord bent state, both ends of the wedge body 20 are located below the long groove 21 as shown by the chain line in FIG. 3. At the same time, the middle is opened between the back surface 18 of the fork 3 and the inclined surface 19 of the inclined plate 22, that is, loosely fitted to the open position. Then, although the fork 3 may rattle in the front-rear direction with respect to the fork support 2, the sliding resistance of the fork 3 with respect to the fork support 2 is reduced accordingly, so that the fork 3 can be easily moved, The interval of 3 can be easily adjusted.

  Since the inclined surface 19, the wedge body 20, and the long groove 21 of the wedge means 4 are all provided in the fork support body 2, it is not necessary to process the fork 3 and the lower hook 17, and there is a possibility that the strength thereof will be reduced. Absent. Not only that, the conventional one can be used as it is, which is extremely reasonable.

Next, a second example of the present invention will be described with reference to FIG.
FIG. 6 is a longitudinal side view showing a fork back-preventing device according to a second example of the present invention.
In the second example, the inclined surface 19 provided on the fork support 2 is different from the first example.
That is, the inclined surface 19 is formed by removing the front upper portion of the lower finger bar 7 by inclining it by a predetermined angle θ.
In such a case, since the inclined surface 19 is formed by using the lower finger bar 7, the inclined plate 22 is not required as in the first example, and the number of parts can be reduced correspondingly, thereby simplifying the structure and cost. Can be reduced.

Next, a third example of the present invention will be described with reference to FIGS.
FIG. 7 shows a fork backlash preventing device according to a third example of the present invention, in which the right half is in a fitted state and the left half is in an open state. FIG. 8 is a longitudinal side view of FIG. 7 showing a fitted state. FIG. 9 is a vertical side view of FIG. 7 showing an open state.

In the third example, the wedge means 4 is different from the first example.
That is, the wedge means 4 is provided on the fork support 2 to form a wedge-shaped space with the back surface 18 of the fork 3, and is lowered to be between the back surface 18 and the inclined surface 19 of the fork 3. A wedge body 20 that can take an insertion position inserted into the fork 3 and an open position that is raised and opened from between the back surface 18 and the inclined surface 19 of the fork 3, and is provided between the fork support body 3 and the wedge body 20. And a guide mechanism 23 for guiding the wedge body 20 so as to be movable up and down.

The inclined surface 19 is formed on the front surface by tilting the center plate 8 provided between the upper and lower finger bars 6, 7 of the fork support 2 backward by a predetermined angle θ.
The wedge 20 has a substantially trapezoidal shape on the front and a thin trapezoid as the cross section goes downward.
The guide mechanism 23 includes a plurality of (two) links 24 and a connecting pin 25 that connects the links 24 so that they can be bent. The upper and lower ends of the guide mechanism 23 are respectively located on the upper front side of the center plate 8 and the upper front side of the wedge body 20. It is pivotally connected by a stop pin 26.

As shown in the right half of FIG. 7 and FIG. 8, when the wedge body 20 is lowered, the wedge body 20 is inserted between the back surface 18 and the inclined surface 19 of the fork 3 to be in the insertion position. Backlash in the front-rear direction is prevented.
On the contrary, as shown in the left half of FIG. 7 and FIG. 9, when the wedge body 20 is raised, it is opened, that is, loosely fitted between the back surface 18 and the inclined surface 19 of the fork 3 to the open position. Although the fork 3 with respect to the fork support 2 may be loose in the front-rear direction, the sliding resistance of the fork 3 with respect to the fork support 2 is reduced accordingly, so that the fork 3 can be easily moved, The interval can be adjusted easily.
In such a case, since the inclined surface 19 is formed using the center plate 8, the number of parts can be reduced. Since the guide mechanism 23 is also composed of the link 24 and the connecting pin 25, the structure is simple.

Next, a fourth example of the present invention will be described with reference to FIG.
FIG. 10 shows a fork rattle prevention device according to a fourth example of the present invention, in which the right half is a fitted state and the left half is an open view.

In the fourth example, the guide mechanism 23 is different from the third example.
That is, the guide mechanism 23 includes an elongated hole 27 and a pin 28 that is engaged with the elongated hole 27.
The long hole 27 is formed in a bracket 29 attached to the upper portion of the wedge body 20, and includes three vertical holes that allow the wedge body 20 to move up and down, and the wedge body 20 in order to keep the wedge body 20 in an open position. It has a substantially horizontal E shape with one horizontal hole.
The pin 28 is a headed bolt or the like so as not to drop out of the long hole 27, and two pins are implanted in the center plate 8. The two pins 28 are provided so as to engage with two of the three vertical holes of the long hole 27.

As shown in the right half of FIG. 10, when the wedge body 20 is lowered, it is inserted between the back surface 18 and the inclined surface 19 of the fork 3 to be an insertion position, and the fork 3 is moved in the front-rear direction. The backlash is prevented. At this time, the two pins 28 are engaged with the center and the left vertical hole of the long hole 27, but may be engaged with the center and the right vertical hole of the long hole 27 depending on the position of the fork 3.
On the contrary, as shown in the left half of FIG. 10, when the wedge body 20 is raised, it is opened, that is, loosely fitted between the back surface 18 and the inclined surface 19 of the fork 3 to be in the open position. Although the fork 3 with respect to the support body 2 may be loose in the front-rear direction, the sliding resistance of the fork 3 with respect to the fork support body 2 is reduced accordingly, so that the fork 3 can be easily moved and the distance between the forks 3 is simplified. Can be adjusted.
In such a case, since the inclined surface 19 is formed using the center plate 8, the number of parts can be reduced. Since the guide mechanism 23 is also composed of the long hole 27 and the pin 28, the structure is simple. In addition, since the long hole 27 of the guide mechanism 23 has a lateral hole for keeping the wedge body 20 in the open position, it is necessary for the operator to hold the wedge body 20 in the open position when the fork 3 is moved. Absent.

In the first example, the inclined surface 19 is formed by providing the inclined plate 22. However, the present invention is not limited to this. For example, as in the third and fourth examples, the center plate 8 is inclined backward and formed on the front surface thereof. You may do it.
In the third and fourth examples, the inclined surface 19 is formed on the front surface of the center plate 8 by tilting backward. However, the present invention is not limited to this. For example, the center plate 8 remains vertical and only the front surface is tilted backward. May be formed.
In the first example, the wedge body 20 has a substantially trapezoidal cross section. However, the wedge body 20 is not limited thereto, and may have a circular cross section, for example.
In the third example and the fourth example, the wedge bodies 20 are arranged in the vicinity of the center plate 8 as a pair on the left and right sides. However, the wedge body 20 is not limited to this and is disposed, for example, in a single lateral movement range of the fork 3. It may be done. In this way, backlash can be prevented even if the fork 3 is laterally moved to an arbitrary position.
In the first example, the long groove 21 is tilted forward so that the upper side is forward and the lower side is rearward. However, the long groove 21 is not limited to this, and may be formed, for example, vertically or backwardly tilted.
In the fourth example of the guide mechanism 23, the long hole 27 is formed in the bracket 29. However, the present invention is not limited thereto, and the long hole 27 may be formed in the wedge body 20 by omitting the bracket 29. In this way, the number of parts can be reduced, and the structure can be simplified and the cost can be reduced.

The front view which shows the insertion state of the backlash prevention apparatus for forks which concerns on the 1st example of this invention. FIG. 2 is a longitudinal side view of FIG. 1. FIG. 2 is a longitudinal side view of FIG. 1 showing a wedge body and a long groove. The same figure as FIG. 1 which shows an open state. The same figure as FIG. 2 which shows an open state. The longitudinal side view which shows the backlash prevention apparatus for forks which concerns on the 2nd example of this invention. The front half shows the backlash prevention device for forks concerning the 3rd example of the present invention, the right half shows an insertion state, and the left half shows an open state. The vertical side view of FIG. 7 which shows an insertion state. The longitudinal side view of FIG. 7 which shows an open state. The front half shows the backlash prevention device for forks concerning the 4th example of the present invention, the right half shows an insertion state, and the left half shows an open state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fork back prevention apparatus, 2 ... Fork support body, 3 ... Fork, 4 ... Wedge means, 5 ... Lift bracket, 6 ... Upper finger bar, 7 ... Lower finger bar, 8 ... Center plate, 9 ... Side plate, DESCRIPTION OF SYMBOLS 10 ... Projection, 11 ... Hanging notch, 12 ... Projection, 13 ... Notch, 14 ... Vertical piece, 15 ... Horizontal piece, 16 ... Upper hook, 17 ... Lower hook, 18 ... Back surface, 19 ... Inclined surface, 20 ... Wedge body, 21 ... long groove, 22 ... guide plate, 23 ... guide mechanism, 24 ... link, 25 ... connecting pin, 26 ... fastening pin, 27 ... long hole, 28 ... pin, 29 ... bracket, [theta] ... predetermined angle.

Claims (5)

A fork support that can be raised and lowered, a fork suspended so as to be laterally movable on the fork support, and a wedge means that is provided on the fork support and can be fitted and opened between the fork support and the fork. The wedge means comprises an inclined surface that is provided on the fork support and forms a wedge-shaped space with the back surface of the fork, and both ends are supported by the fork support and the middle is the back surface and the inclined surface of the fork. And an insertion position where both ends are supported by the fork support and an intermediate position is opened from between the back surface and the inclined surface of the fork and becomes a lower string bending state. A fork rattle prevention device comprising an arcuate wedge body that can be elastically deformed . A fork support that can be raised and lowered, a fork suspended so as to be laterally movable on the fork support, and a wedge means that is provided on the fork support and can be fitted and opened between the fork support and the fork. The wedge means is provided on the fork support and forms a wedge-shaped space with the back surface of the fork; and a fitting position where the wedge means is lowered and fitted between the back surface and the inclined surface of the fork. A wedge body which can be lifted and can be opened from the back surface and the inclined surface of the fork, and a guide mechanism which is provided between the fork support body and the wedge body and which guides the wedge body so as to be movable up and down. A fork back-preventing device characterized by comprising: The backlash prevention device for a fork according to claim 2, wherein the guide mechanism includes a plurality of links and a connecting pin that connects the links in a refractive manner. The rattle prevention device for a fork according to claim 2, wherein the guide mechanism includes an elongated hole and a pin engaged with the elongated hole. 5. The rattle prevention device for a fork according to claim 4, wherein the elongated hole includes a vertical hole that allows the wedge body to move up and down, and a horizontal hole that keeps the wedge body in an open position.

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