JPH0633383Y2 - Joint mechanism of inner part copper lifting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a device for raising and lowering a calibration weight housed in a weighing device, and in particular to an elevator device configured to raise and lower an annular calibration weight. Regarding the joint mechanism.

[Technical background of the invention]

When the weighing device is used for a long period of time, the display of the weight may be inaccurate due to slight looseness or slight deviation of the internal mechanism. The same thing occurs due to vibrations and the like during transportation of the weighing device. In this case, in order to calibrate the weight display of the weighing device to an appropriate value, it is necessary to adjust the display using a calibration weight whose accurate weight is known in advance. The calibration work
This is a method of calibrating by placing a calibration weight on a weighing pan. However, in this method, it is necessary to store and store the calibration weight separately from the weighing device, and to take out the calibration weight for each calibration, which is inconvenient to handle. For this reason, the calibration weight is stored in the weighing device in advance, and when calibration is required, the calibration weight is stored in the weighing device by an operation from outside the device (hereinafter referred to as "built-in weight"). There is provided a mechanism for performing calibration by transmitting the load of 1 to the load transmitting portion of the weighing object.

In this regard, the inventors have previously proposed an inner copper lifting device that can perform calibration easily and accurately (Japanese Patent Application No. 62-309).
No. 723).

FIG. 3 shows the internal weight lifting mechanism. In the figure, reference numeral 1 indicates a large (large weight) built-in weight, and 2 indicates a small (lightweight) built-in weight. As is apparent from the figure, the built-in weights 1 and 2 are each formed in a plane annular shape and are arranged concentrically by a supporting member described later. Reference numeral 3 is a support member that supports these built-in weights 1 and 2 and moves them up and down. 3a, 3b, 3c
Is a built-in weight support arm extended from the support member frame 3d having a substantially "U" shape in plan of the support member 3 to the inside of the frame. The built-in weights 1 and 2 are concentrically arranged so that their centers are made common by being supported by the support arms 3a, 3b, 3c, and the common center transmits the load of the weighing object to the beam side. It is arranged so as to coincide with the axis of the load transmission shaft.

Next, at the four corners of the frame 3d of this support member, support pins 4a, 4b,
4c and 4d are inserted. The lower end of this pin is fixed to the main body of the weighing device, and the supporting member 3 moves up and down along the pin while keeping the internal weights 1 and 2 in a horizontal state along the axis of the load transmission shaft. It is like this. 3e, 3f
Is a lifting / lowering projecting piece that is located at a projecting position on opposite sides of the frame 3d, and the lifting / lowering mechanism makes contact with and engages with the lifting / lowering protruding pieces 3e, 3f. The built-in weights 1 and 2 supported by the are moved up and down.

The lift mechanism for the support member will be described. Reference numeral 5 is a rotary shaft that is rotated by a geared motor 6, and a first cam 7 and a second cam 8 are provided for the rotary shaft 5. Of the two cams provided on the rotary shaft 5, the first cam 7 is the support member 3
Of the second cam 8 which is in contact with the lower surface of the ascending / descending projection 3f.
Is in contact with the lower surface of one end of the first oscillating plate 10 forming a part of the lifting motion transmission mechanism. The end of the swing plate 10 on the side facing the cam 8 contact side swings in the X1-Y1 direction by a fulcrum 11. Next, 12 is arranged so as to form a right angle with respect to the first oscillating plate 10 and the fulcrum 13 causes the protrusion
3e is a second oscillating plate whose end on the side in contact with 3e is oscillated in the X2-Y2 direction, and the end on the side in contact with the first oscillating plate is the lower surface of the first oscillating plate 10. It is arranged so as to come into contact with.

In the above configuration, first, the built-in weights 1 and 2 are raised so that no load is applied to the floating frame (not shown) that is a load transmission member for the electromagnetic unit side, that is, a state in which the load of the weighing object can be measured. To do this, operate as follows.

First, by operating the geared motor 6, the first and second cams 7 and 8 are rotated via the rotary shaft 5.
First, the first cam 7 will be described. When the first cam 7 rotates, the protrusion 3f contacting the cam 7 is pushed upward in the X3 direction. Similarly, one of the ends of the up-and-down motion transmission mechanism pushes up the cam contact end of the first rocking plate 10 in contact with the second cam 8. As a result, the opposite end is centered on the fulcrum 11, Y1
In the same direction, the end of the second rocking plate 12 is pushed down in the same direction. As a result, the end of the second rocking plate 12 on the side of the protrusion 3e rises in the X2 direction and pushes up this protrusion in the same direction. That is, the protrusions 3e and 3f are simultaneously pushed up by the rotation of the cams 7 and 8. By this operation, the support member rises along the pins 4a to 4d, and the built-in weights 1 and 2 supported by the support member rise while maintaining the horizontal state. Then, the rotation of the cam is stopped in the raised state to support each built-in weight. As a result, all the loads of the built-in weights 1 and 2 are supported by the supporting member 3, and only the load of the weighing object placed on the weighing pan is transmitted to the floating frame which is a member for transmitting the load.

When calibrating next, perform the following operations.

By operating the geared motor 6, the first and second cams 7 and 8 are rotated again. As a result, the support member 3 is gradually lowered by the operation opposite to the above-described rising operation. Since the support heights of the respective built-in weights 1 and 2 by the support member 3 are different in advance, the lower surface of the small built-in weight 2 is first placed on the floating frame by this lowering, and the load of this weight 2 is applied to the floating frame. Will be transmitted. Further, the support member 3 is lowered to place the large built-in weight 1 on the floating frame, and the loads of both weights 1 and 2 are transmitted to the floating frame. That is, when calibrating the precision weighing mode of the weighing device, only the small built-in weight 2 is placed on the floating frame 14. As a result, accurate calibration can be performed with the small built-in weight 2 having a weight suitable for calibration in the precision weight measurement mode. When the calibration in the large weight measurement mode is performed, the calibration is performed by the total load of the small built-in weight 2 and the large built-in weight 1.

[Problems to be solved by the device]

In the built-in weight lifting mechanism specifically described above, the built-in weight lifting mechanism and the mechanism of the weighing device incorporating this mechanism,
There is no space for arranging the motor, which is a drive source for moving up and down the built-in weight, near this lifting mechanism. For this reason, the motor itself is arranged at a position far away from the lifting mechanism, and the long rotary shaft 5 is used to transmit the driving force. Since such a long rotating shaft is used, there is a possibility that the shaft may bend during rotation, or the rotating shaft of the motor and the shaft center of the rotating shaft 5 may deviate over time. When such bending or deviation occurs, a large load is applied to the motor, which causes problems such as heat generation of the motor, generation of abnormal noise, malfunction, and shortening of the life of the device. For this reason, bearings are arranged in several places with respect to the rotary shaft to hold the rotary shaft, but this is not a fundamental solution to the problem.

[Means for Solving the Problems]

The present invention is configured in view of this technical problem, and a joint is arranged between a long rotary shaft and a rotary shaft of a motor, and the rigidity of the joint is lower than those of the rotary shaft and the motor rotary shaft. The joint mechanism of the built-in weight lifting device configured to absorb the stress to be applied to the motor at the joint portion.

[Action]

The joint interposed between the motor and the rotary shaft absorbs the stress generated by the bending of the rotary shaft and the misalignment of the shaft center between the rotary shaft and the motor rotary shaft, and the joint absorbs the stress. Make sure that no special stress is applied to.

〔Example〕

 Embodiments of the present invention will be specifically described below with reference to the drawings.

In FIG. 1, 20 is a rotary shaft 6a of a motor (geared motor) 6 and a rotary shaft 5 that transmits the rotary force of this motor to a built-in weight lifting mechanism (hereinafter referred to as "rotary force transmitting shaft" to distinguish it from the rotary shaft of the motor). (Referred to as) and a joint arranged between the two. This joint 20 is a connecting portion 20 which is inserted through the rotary shaft 6a of the motor 6 and arranged.
a, a connecting portion 20b connected to the rotational force transmitting shaft 5 side, and a stress absorbing and rotational force transmitting shaft 20c arranged between these connecting portions. The stress absorbing shaft 20c is a shaft thinner than the rotary shaft 6a and the rotary force transmitting shaft 5 in the configuration shown in the figure. Therefore, when the stress absorbing shaft 20c is made of the same material as those of the rotary shaft 6a and the rotary force transmitting shaft 5, these respective The rigidity is lower than that of the shafts 6 and 5. As a result, when stress is applied to the motor 6 side due to bending of the rotational force transmitting shaft 5 during rotation, misalignment of the rotational center of the rotational force transmitting shaft 5 and the motor-side rotating shaft 6, or the like, the stress absorbing shaft with the lowest rigidity Stress concentrates on 20c,
The shaft 20c deforms and absorbs all the stress.

The connecting members 20a and 20b of the joint 20 are connected to the rotary shaft 6a and the rotary force transmitting shaft 5 with screws or the like.
The method can be appropriately selected such as simply inserting.

FIG. 2 shows another embodiment.

In the case of this embodiment, instead of disposing a rod-shaped shaft between the connecting members 20a and 20b, a coil spring 21 is disposed. This coil spring 21 is closely attached to the spiral wire forming the spring,
It always acts like a rod-shaped shaft, but when stress is applied, it acts as an elastic body and deforms according to the stress to absorb the stress. In the case of this configuration, the shaft body that transmits the rotational force between the two shafts 5 and 6a is basically an elastic body, so that the stress can be absorbed better.

Although the joint is arranged between the rotating shaft 6a of the motor and the rotational force transmitting shaft 5 in the above configuration, the present invention is not limited to this configuration and the motor rotating shaft 6 and the rotational force transmitting shaft 5 absorb stress. It is possible to achieve substantially the same purpose by connecting with a joint mechanism that is not possible, dividing the rotational force transmission shaft 5 into, for example, two, and connecting the divided portion with the joint.

〔effect〕

According to the present invention, a joint is arranged between a large rotational force transmitting shaft and a motor rotating shaft, and the rigidity of the joint is made lower than that of the rotating shaft and the motor rotating shaft, and the joint is applied to the motor. Since it is configured to absorb the expected stress, the joint part absorbs the stress generated by the bending of the rotational force transmission shaft and the deviation between the rotational force transmission shaft and the motor rotational shaft, so that the motor is not loaded. In addition to prolonging the life of the device, problems such as heat generation of the motor, generation of abnormal noise, malfunction, etc. do not occur.

[Brief description of drawings]

FIG. 1 is a plan view of an internal weight lifting device in a weighing device showing an embodiment of the present invention, FIG. 2 is a side view of a joint showing another embodiment, and FIG. 3 is a working state of the internal copper lifting device. It is a perspective view. 1 ... Large inner copper, 2 ... Small inner copper 5 ... Rotation force transmission shaft, 6 ... Motor 6a ... Motor rotating shaft, 20 ... Coupling 20a, 20b ... Connector, 21 ... Coil spring

Claims (3)

[Scope of utility model registration request] Claim: What is claimed is: 1. A rotational force transmission shaft for transmitting rotational force to an inner part copper lifting mechanism, and a joint is arranged between the rotational force transmission shaft and a motor side for generating the rotational force, and the joint is constructed. The inner part copper lifting / lowering is characterized in that the rigidity of the rotating force transmitting member is at least lower than the rigidity of the rotating shaft on the motor side, and the stress to be applied to the motor is absorbed by the rotating force transmitting member of this joint. Device joint mechanism. 2. A joint mechanism for an internal copper lifting device, wherein the rotational force transmission shaft is divided into two parts, and the joint is arranged in the divided part. 3. A joint mechanism for an internal copper lifting device according to claim 1 or 2, wherein the torque transmitting member of the joint is formed of a coil spring.