JP2533991Y2 - Dish positioning mechanism for balance - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pan positioning mechanism for a scale using, for example, a load cell type as a load sensor.

[0002]

2. Description of the Related Art In a load cell type balance or the like,
Generally, a dish receiving shaft is fixed to a sensitive part of a load sensor such as a load cell, and the dish receiving shaft is detachably supported by the dish receiving shaft, and a sample mounting dish is mounted on the dish receiving shaft. Has been adopted. In the scale having such a structure, it is necessary to position the edge of the plate 4 parallel to each side of the main body case C as shown in an external view in FIG. As a positioning mechanism for
Conventionally, a method using a leaf spring, a method using fitting of unevenness, and the like are known.

In the case of the plate spring, a notch is provided in a part of the plate receiving shaft, and a plate spring is provided on the plate receiving side so as to be in close contact with the notch portion. The structure is such that a force is applied by which the dish receiver returns to the original direction by the action of the spring. In addition, the fitting by the unevenness has a structure in which the unevenness is formed so as to be fitted to the dish receiving shaft and the dish receiving axis.

[0004]

[Problems to be Solved by the Invention] By the way, in the above-described conventional positioning mechanism using a leaf spring, when the plate and the plate receiver are rotated with respect to the disk receiving shaft to a certain degree or more, the force of the plate spring is increased. In such a case, there is a problem that restoration becomes impossible and the dish stops in an unstable state. Further, in the case of using the fitting of the unevenness, when a force for rotating the plate is applied from the outside, the shock cannot be absorbed, and there is a problem that the weighing mechanism is damaged.

An object of the present invention is to provide a weighing dish which is difficult to stop in an unstable state, and which is not transmitted to the weighing mechanism even when an external force in the direction of rotating the weighing works, and which has good impact resistance. It is to provide a positioning mechanism.

[0006]

Means for Solving the Problems In order to achieve the above object, according to the present invention, a plate support is rotatably supported on a plate support shaft around its axis, and the plate support shaft and the plate are supported. Magnets are fixed to the opposite surfaces of the receiver so that the opposite polarities face each other.

[0007]

The rotating position of the plate receiver is regulated by the attraction force of the magnets disposed opposite to the plate receiving shaft. The pan support is rotatably supported by the pan support shaft, so that when an external force acts in the direction to rotate the pan, the pan receiver rotates freely and the force is transmitted to the weighing mechanism. There is no. Further, since the notch or the like is not formed on the dish receiving shaft and no force is exerted on the dish receiving shaft from the lateral direction, the dish or the dish receiver does not stop at an unstable position.

[0008]

FIG. 1 is an exploded front view of a main part of an embodiment of the present invention.
FIG. 2 is a plan view of the dish receiving shaft 1. The dish receiving shaft 1 is fixed to the upper surface of the sensitive part of the load cell 5. The dish receiving shaft 1 includes a tapered portion 11 and a step portion 12 formed on the lower end large diameter side of the tapered portion 11. Two permanent magnets 2a and 2b are embedded in the upper surface of the step portion 12. The permanent magnet 2a has an N pole,
The permanent magnets 2b are embedded with their S poles facing upward.

The plate receiver 3 is formed by integrally forming a flat portion 31 for supporting the plate 4 and a projecting portion 32 at the center of the lower surface of the flat portion 31. The projecting portion 32 has a dish receiving shaft. A concave portion 33 into which the first tapered portion 11 fits is formed,
The dish receiver 3 is rotatably supported about the axis of the dish receiver shaft 1 with the tapered portion 11 fitted in the recess 33. Two permanent magnets 2c and 2d are embedded at the same pitch as the upper surface of the step portion 12 of the dish receiving shaft 1 on the lower end surface of the projecting portion 32 of the dish receiving 3 and the permanent magnet 2c has an S pole. Down, and a permanent magnet 2d
Indicate that the N pole faces downward.

In a state where the plate receiver 3 is supported in a normal direction with respect to the plate receiver shaft 1, the permanent magnets 2a and 2c are opposed to the permanent magnets 2b and 2d as shown in FIG. I have. According to the structure of the embodiment of the present invention described above, when the pan receiver 3 is mounted on the pan support shaft 1, the permanent magnets 2a and 2
Due to c and the suction force of 2b and 2d, the pan receiver 3 is always positioned so as to be in the correct orientation, and at the same time, the position of the pan 4 placed thereon is determined.

When an external force acts on the plate 4 in a direction for rotating the same, if the force exceeds the attraction force of each permanent magnet, the plate receiver 3 rotates with respect to the plate receiving shaft 1. This force is released, and the force does not reach the weighing mechanism including the load cell 5. In addition, no notches are formed in the pan support shaft 1 and the pan support 3, so that there is no position where the pan support 3 becomes unstable at a position other than the normal position.

In the above-described embodiment, two permanent magnets are provided on each of the dish receiving shaft 1 and the dish receiving 3, but the number of permanent magnets may be one or three or more. Of course.

[0013]

[Effect of the Invention] As described above, according to the present invention,
The pan support is rotatably supported with respect to the pan support shaft, and magnets are provided on the opposing surfaces of the pan support shaft and the pan support so that their polarities are opposite to each other. Since the pan support is always supported in the correct direction with respect to the pan support shaft, the pan support is free even if an impact force is applied to the pan or pan support from the side in the direction to rotate them. To release the force and exert a buffering function on the weighing mechanism. Further, unlike the mechanism using the conventional leaf spring, there is no position where the dish receiver is in an unstable state.

[Brief description of the drawings]

FIG. 1 is an exploded sectional view of a main part of an embodiment of the present invention.

FIG. 2 is a plan view of the dish receiving shaft 1.

FIG. 3 is an external view showing an example of a scale to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Dish receiving shaft 11 ... Taper part 12 ... Step part 2a, 2b, 2c, 2d ... Permanent magnet 3 ... Dish receiving 31 ... Flat part 32 ····· Projection 33 ··· Recess 4 ··· Plate 5 ··· Load cell

Claims (1)

(57) [Scope of request for utility model registration] 1. A scale in which a plate receiver is detachably mounted on an upper end surface of a plate receiver shaft fixed to a load sensor, and a plate is placed on the plate receiver. The balance is supported rotatably about its axis, and magnets are fixed to opposite surfaces of the dish receiving shaft and the dish receiving so that opposite polarities are opposed to each other. Dish positioning mechanism.