JPH06562B2 - Drive device for raising and lowering traveling crane - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lifting and lowering carriage drive device for a traveling crane used for loading and unloading work with respect to shelves in an automatic warehouse.

(Prior art and its problems) As an elevator carriage drive device in this type of traveling crane, a chain with both ends locked to the elevator carriage is stretched in a loop along the carriage elevator path, A carriage drive device is known in which an intermediate portion is engaged with a drive tooth wheel in a drive unit, and the carriage is raised and lowered by forward and reverse rotation of the chain.

Such a loop chain type carriage drive was used for a light load crane, but when the weight of the load to be handled increases, it is necessary to also use a counterweight to reduce the load on the lifting drive motor. There is. In such a case, the conventional loop chain type carriage drive can connect the counterweight to the carriage driven up and down in a fishing bottle system through a dedicated chain, but the number of chains used (total length) increases. And it is uneconomical.

In addition, the chain that suspends the lifting carriage is in tension because the tension is always applied even if it extends, but the return chain that hangs from the lifting carriage is the extension of the carriage hanging chain or the return chain itself. Will be relaxed as it grows. This loosening of the return side chain may lead to extremely serious accidents such as the chain coming off from the drive teeth or guide teeth when driving the carriage up and down, and must be absolutely prevented. It has been considered that a take-up mechanism that pulls up the return-side chain and tensions the return-side chain is provided at a position where the side chain is connected to the lifting carriage.

With such a configuration, the weight of the chain on the return side hanging from the carriage acts as a load on the chain lifting spring in the take-up mechanism, so a spring with a large elastic force is required, and the take-up This leads to an increase in the size of the mechanism and an increase in cost.
Further, a large operation force is required for the operation for adjusting the elastic force of the spring, which makes the work difficult.

(Means for Solving Problems) The present invention is intended to solve the problems of the conventional configuration as described above, and the features of the carriage drive device of the present invention will be described later. If the reference numerals of the examples are given in parentheses, the lifting carriage drive device of the present invention is loosely fitted in the right and left ends of the lifting carriage (9) and the column (8a) beside the carriage lifting path so as to be liftable. The two chains for hanging the carriage (11A, 12A) that suspend the counterweight (W) at both ends, and the chain on the return side where both ends are connected to the lifting carriage (9) and the counterweight (W). (11B, 12B), chain drive tooth wheel (17, 18),
The chain drive movable wheels (19, 20) and the chain drive tooth wheels (17, 18) and the chain take-up movable wheels (19, 20) are arranged on the lower end side of the carriage lifting path. It is characterized in that it is installed and engages with the return side chain (11B, 12B).

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying illustrative drawings. In FIGS. 1 and 2, reference numeral 1 is a crane lower frame, which is laid on the floor surface. A drive wheel 3 and driven wheels 4 that roll on the lower guide rail 2 are provided. Reference numeral 5 denotes a crane upper frame having a vertical shaft roller 7 for steadying, which engages with an upper guide rail 6 installed on the ceiling side, and which is provided on the lower frame 1 via a pair of vertical columns 8a and 8b. It is connected. 9 is a pillar 8
It is a lift carriage supported so as to be lifted between a and 8b, and a load transfer means 10 such as a running fork is mounted.

As shown in FIGS. 2 and 5, the lifting carriage 9
Carriage hanging chains 11A, 1 at the front and rear ends
One ends 11a and 12a of 2A are locked. One of the chains 11A is turned downward by a guide toothed wheel 13 that is axially supported inside one end of the upper frame 5, and then the support column 8a.
The other chain 12A is introduced into the other end of the upper frame 5 via a guide toothed wheel 14 axially supported inside the other end and a guide toothed wheel 15 supported coaxially with the guide toothed wheel 13. It is introduced into the pillar 8a.

The free ends of the chains 11A and 12A introduced into the support column 8a are connected to the upper ends of the counterweights W that are loosely fitted in the support columns 8a so that they can be returned to the lower ends of the counterweights W. One ends of the side chains 11B and 12B are connected.

The return side chains 11B and 12B are shown in FIGS.
As shown in FIGS. 5 and 5, it is guided into the lower frame 1 through an opening 16 formed across the lower end of the column 8a and the upper surface of the lower frame 1. Then, the drive toothed wheels 17, which are coaxially integrated and are axially supported in the lower frame 1,
18 is engaged with movable take-up teeth 19, 20 coaxial with 18 via guide teeth 21-26, respectively, and then an opening 27 provided on the upper surface of the lower frame 1 inside the column 8a. In the chains 11B and 12B guided to the upper part of the lower frame 1 again, the free ends 11b and 12b of the chains 11B and 12B along the support column 8a have the support column 8a of the lifting carriage 9 respectively.
Is locked at a position adjacent to.

The take-up movable toothed wheels 19 and 20 constitute a chain take-up mechanism 28 that also serves as a disconnection detection mechanism for the return-side chains 11B and 12B, and the mechanism 28 is the take-up movable toothed wheel. 19, 20,
Two bearings 29 that individually support the movable toothed wheels 19 and 20, respectively, are movably supported in the length direction of the lower frame 1 (the traveling direction of the crane), and the bearings 29 are separately provided at the tips. 2 guide rods 30, two springs 31 for individually biasing each guide rod 30 in the chain tension direction, a switch operating piece 32 attached to each guide rod 30, and two limit switches 33. There is.

The two limit switches 33 individually detect, via the switch operation piece 32, that the movable toothed wheels 19 or 20 have moved by a certain amount due to the urging force of the spring 31 due to the disconnection of the return side chain 11B or 12B. To do.

On the other hand, the carriage hanging chains 11A, 12A
At the connecting point between the ends 11a and 12a of the sill and the lifting carriage 9, the hanging chain cutting detection mechanism 34 shown in FIG.
Are installed respectively. Each of the hanging chain cutting detection mechanisms 34 is supported by the lifting carriage 9 so as to be able to move up and down, and the lifting guide rod 35 having the chain 11A or 12A locked at the upper end is attached to the lifting guide rod 35 in the descending direction. Biasing spring 36, switch operation piece 3 attached to the lower end of the elevating guide rod 35
7, and a limit switch 38 for detecting, via the switch operating piece 37, that the lifting guide rod 35 has descended by a certain amount due to the urging force of the spring 36 when the chain 11A or 12A is cut.

Reference numeral 39 is a motor for driving the drive wheel 3 in forward and reverse directions, and 40 is a motor for driving the drive teeth 17, 18 in forward and reverse directions.

The traveling crane configured as described above can travel along the lower guide rail 2 by rotating the drive wheels 3 by the motor 39. Then, when the elevating carriage 9 is moved up and down to a desired loading / unloading work level, the drive toothed wheels 17, 18 are rotated by the motor 40. As a result, both ends 11a, 11b and 12a, 12b
Is locked to the lifting carriage 9 and has a counterweight W in the middle thereof, which is a loop-shaped chain 11A, 11
B and 12A, 12B rotate, and the lifting carriage 9 moves up and down along the columns 8a, 8b. At this time, the counterweight W moves up and down in the opposite direction over the entire length of the support column 8a as the lift carriage 9 moves up and down.

Elevating carriage 9 is chain 11A, 11B as described above.
And 12A, 12B, the take-up mechanism 2 is attached to the return side chains 11B, 12B.
The urging force of the spring 31 of No. 8 acts separately via the movable toothed wheels 19 and 20, and a substantially constant tension is always applied. Further, since the movable tooth wheels 19 and 20 act as a moving pulley, the movable tooth wheels 19 and 20 are connected to the chains 11B and 12B.
The pulling length (take-up allowance) is a movable toothed wheel 19,2
The length is twice the moving distance of 0.

If the chain 11A or 12A that suspends the lift carriage 9 is cut for any reason, the lift guide rod 35 connecting the broken chain 11A or 12A to the lift carriage 9 is lowered by the urging force of the spring 36. , The operation of the switch operating piece 3
Since the limit switch 38 is detected via 7, it is possible to detect a disconnection accident of the hanging chain 11A or 12A from the detection operation of the limit switch 38.

Further, when the return side chain 11B or 12B is cut for some reason, the movable toothed wheel 19 or 20 hanging on the broken chain 11B or 12b is urged by the spring 31 to move together with the guide rod 30 at a constant distance. Since the limit switch 33 detects the movement through the switch operation piece 32, the return side chain 1 is detected from the detection operation of the limit switch 33.
A 1B or 12B disconnection accident can be detected.

The take-up movable toothed wheel 1 for tensioning the return chains 11B and 12B adopted in the above embodiment.
Detecting mechanism (switch operation piece 32, limit switch 33) for detecting movement of 9, 20 when the chain is cut off, and detection for detecting disconnection of the carriage hanging chains 11A, 12A at the connecting portion with the lifting carriage 9. The mechanism 34 is
It is not essential to the invention.

However, when these are installed side by side as in the embodiment, the cutting of the hanging chains 11A and 12A for suspending the counterweight W and the lifting carriage 9 must be reliably detected by the chain cutting detection mechanism 34 on the lifting carriage 9 side. , The return side chains 11B, 12B are cut using the chain take-up movable toothed wheels 19, 20 for tensioning the return side chains 11B, 12B from the drive toothed wheels 17, 18 to the elevating carriage 9. The detection mechanism (switch operation piece 32, limit switch 33) can surely detect.

(Operation and Effect of the Invention) As described above, the lifting carriage drive device according to the present invention is
Since a counterweight is installed in the middle position of the carriage lifting drive chain stretched in a vertical loop along the carriage lifting path, it is not necessary to use a separate chain dedicated to suspending the counterweight and it is inexpensive. However, according to the configuration of the present invention, the following special operational effects can be obtained.

That is, the hanging return-side chain, whose both ends are connected to the lifting carriage and the counterweight, loosens as the carriage-hanging chain stretches and the return-side chain itself stretches. When the side chain becomes loose, the take-up movable toothed wheel engaged with the return chain moves so as to absorb the slack in the return chain, so that the return chain is always properly tensioned. It will be.

Therefore, there is no fear that the hanging return-side chain will loosen and accidentally come off from the drive toothed wheel or the guide toothed wheel, and the elevator carriage can always be raised and lowered safely and reliably.

Moreover, the return side chain is not pulled up by the spring force to the tension carriage side to be tensioned, but is engaged with the take-up movable toothed wheel arranged at the lower end side of the carriage elevation path. Regardless of the moving direction of the movable tooth ring, the weight of the return side chain hanging from the carriage or the counterweight does not act as a load on the spring that biases the movable tooth ring in the chain tension direction. Therefore, the elastic force of the spring that urges the take-up movable toothed wheel in the chain tension direction is small, and the momentum of the movable toothed wheel is increased in order to tension the chain by using the movable toothed wheel that is a moving pulley. Coupled with the fact that the tension is at least half, even if the crane has a high lift, it is possible to reduce the size and cost of the entire take-up mechanism. Furthermore, the initial tension applied to the return side chain can be easily adjusted because a spring having a small elastic force can be used.

[Brief description of drawings]

Fig. 1 is a side view of the entire crane, Fig. 2 is an enlarged side view with a cutout of the same part, Fig. 3 is a plan view of the crane lower frame, Fig. 4 is an enlarged vertical side view of a main part, and Fig. 5 is a carriage. FIG. 6 is a perspective view showing a tensioned state of the hanging chain, and FIG. 6 is a side view showing a cutting detection mechanism of the carriage hanging chain. 1 ... Crane lower frame, 3 ... Drive wheels, 8a, 8b
... Pillars, 9 ... Elevating carriages, 11A, 12A ... Carriage hanging chains, 11B, 12B ... Return side chains, 13-15, 21-26 ... Guide tooth wheels, 16, 27
... Apertures, 17,18 ... Drive teeth, 19,20 ... Movable teeth for take-up, 28 ... Chain take-up mechanism, 2
9 ... Bearing, 30, 35 ... Guide rod, 31, 36 ... Spring, 32 ... Switch operation piece (return side chain disconnection detection mechanism), 33 ... Limit switch (return side chain disconnection detection mechanism), 34 ... Hanging chain disconnection Detection mechanism, 37 ... Switch operation piece, 38 ... Limit switch.

Claims (1)

[Claims] 1. Carrying two carriages for suspending the left and right ends of a lift carriage (9) and a counterweight (W) loosely fitted in a support (8a) beside the carriage lift path at both ends. Chain (11A, 12A) and lifting carriage
(9) and counterweight (W) are connected at both ends and hang down on the return side chain (11B, 12B) and chain drive tooth ring (1
(7,18) and movable teeth for chain take-up (19,20), the chain drive teeth (17,18) and movable teeth for chain take-up (19,20) move up and down the carriage. An elevating carriage drive device for a traveling crane, which is disposed at the lower end side of the path and engages with the return side chain ((11B, 12B)).