JP2612428B2 - Calibration device for hardness tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calibration for a hardness meter used to calibrate a hardness meter for measuring the strength of a substance, in particular, the hardness (breaking strength) of a compression molded substance such as a tablet or solid feed. It concerns the device.

[0002]

2. Description of the Related Art In order to ensure the quality of tablets, their weight, thickness and hardness are regularly measured. Such a measuring device for measuring the specifications of tablets performs calibration periodically in order to maintain measurement accuracy. Among them, the hardness is measured by applying pressure to the tablet and recording the pressure applied when the tablet is broken to indicate the hardness. An instrument for measuring hardness by measuring such a burst pressure is a hardness meter.

[0003] The hardness tester includes, for example, a sample table, a pressure tip for pressing a tablet placed on the sample table, a geared motor for raising and lowering the pressure chip, and a pressure sensor provided under the sample table to detect pressure. And a recording device that displays and stores the breaking pressure of the tablet based on an electric signal output from the load cell. To measure the hardness, a tablet to be measured is placed on a sample table, and the pressing tip is lowered until it comes into contact with the tablet, and then the pressing tip is further lowered to break the tablet. During this time, pressure is applied to the load cell in accordance with the drop of the pressure tip, and an electric signal is output to the recording device according to the pressure. The electrical signal is maximum just before the tablet is destroyed,
After the destruction, it rapidly decreases. For example, the maximum value is held and displayed and recorded by a peak hold circuit.

[0004]

In such a hardness tester, the measurement cannot be performed unless the sample is destroyed. Therefore, when performing calibration, it is necessary to prepare a standard sample that is destroyed at a known pressure, which becomes a standard device such as a standard weight for a weighing device and a thickness gauge for a thickness measuring device. However, when the sample is destroyed,
Since the sample cannot be used repeatedly for calibration, conventionally a load cell is mounted on the sample table instead of the standard device, and the electric signal output by the load cell mounted on the sample table and the load cell of the hardness meter output Calibration was performed so that the electrical signal to be matched would match.

However, in the calibration using such a load cell, although the pressure applied to the destruction can be calibrated with high accuracy, the pressure at the time of the destruction cannot be measured. That is, since the load cell is not broken like a tablet, it is not possible to realize the breaking pressure as in the actual hardness measurement. Therefore, the calibration of the measurement process portion that requires the most calibration can be performed only insufficiently.

An object of the present invention is to solve such a problem.

[0007]

In order to achieve the above object, the present invention takes the following measures. That is, the calibration device for a hardness tester according to the present invention is provided with a resettable detent mechanism which is separated by a predetermined pressure at one end, and has a pressure receiving portion for receiving pressure from the outside at the other end. A pressure transmission mechanism is provided between both ends for transmitting the pressure applied to the pressure control mechanism to the moderation mechanism and for eliminating the pressure in the pressure receiving portion almost instantaneously when the moderation mechanism separates.

As a desirable mode of the pressure transmission mechanism and the moderation mechanism, the pressure transmission mechanism includes a fixed frame and a movable arm rotatably supported on the fixed frame via a shaft, and the moderation mechanism includes the fixed frame. A ball plunger attached to one end of the movable arm and a ball receiver attached to one end of the movable arm and capable of engaging with the ball plunger.

[0009]

With such a construction, the pressure applied to the pressure receiving portion is transmitted to the moderating mechanism by the pressure transmitting mechanism, and when the pressure reaches a predetermined pressure set in the moderating mechanism, the moderating is performed. The mechanism separates, and the pressure in the pressure receiving portion disappears almost instantaneously. That is, in the pressure receiving section, a pressure equivalent to an external pressure exists until the pressure transmitted to the moderation mechanism reaches the predetermined pressure, and when the predetermined pressure is transmitted to the moderation mechanism, the pressure transmission mechanism As a result, the pressure disappears almost instantaneously, and there is no pressure irrespective of the external pressure. This means that when a change in pressure at the pressure receiving portion is observed, pressure is applied to a substance such as a tablet, and a state equivalent to a state where the substance is destroyed by reaching a certain pressure is reproduced. Therefore, the calibration at the burst pressure can be performed with high accuracy.

Further, since the detent mechanism can be reset, once it is separated, if it is reset, it does not separate until a predetermined pressure is applied again. That is, by resetting the moderation mechanism, it is possible to recover the expected state.
Therefore, once the calibration mechanism is used once, the moderation mechanism is reset, so that it can be used repeatedly.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

The calibration device 1 for a hardness meter shown in FIG. 1 has a resettable moderation mechanism 2 which is separated by a predetermined pressure at one end 1a, and a pressure receiving portion 3 which receives an external pressure is connected to the other end. A pressure transmitting mechanism 4 for transmitting pressure applied to the pressure receiving section 3 to the moderation mechanism 2 and for eliminating the pressure in the pressure receiving section 3 almost instantaneously when the moderation mechanism 2 is separated from each other at both ends; It is provided between the parts 1a and 1b.

The moderating mechanism 2 is, as shown in FIGS.
It comprises a ball plunger 6 attached to one end of a fixed frame 5 described later, and a ball receiver 8 attached to one end of a movable arm 7 described later and capable of engaging with the ball plunger 6. As shown in FIG. 5, the ball plunger 6 has a cylindrical main body 62 having a threaded portion 61 threaded on the outer periphery, and a spring 63 housed in the main body 62.
And the main body 6 urged outward by the spring 63.
2 and a ball 64 housed in the main body 62 with the outer end exposed. The ball plunger 6 is fixed by screwing a screw portion 61 of a main body 62 to one end of the fixed frame 5. As shown in FIG. 5, the ball receiver 8 is formed by drilling a cone-shaped hole 81 at the center of one end of a solid cylindrical shape with its apex facing inward. 6 are engaged with the ball 64. That is, the ball 64 is engaged with the ball receiver 8 at its outer end so as to be separated by a predetermined pressure.

The pressure receiving portion 3 is made of a super-hard material having excellent wear resistance, and includes a pressure receiving surface 31 for receiving pressure and a downward surface 32 placed on a sample table B of a hardness meter A described later. The pressure receiving surface 31 is integrally formed on one end of the movable arm 7 described later in a convex shape that curves upward, that is, in a semicircular shape when viewed from the front. The downward surface 32 is integrally formed in a planar shape at one end of a fixed frame 5 described later. That is, the pressure receiving surface 31 is supported by the fixed frame 5 so as to be movable up and down via the movable arm 7 and the shaft 9.

The pressure transmission mechanism 4 includes a fixed frame 5 and a shaft 9
And a movable arm 7 rotatably supported by the fixed frame 5 via a shaft 9, and transmits the pressure applied to the pressure receiving surface 31 to the moderation mechanism 2 as a pressure in a direction opposite to the pressing direction.

As shown in FIGS. 1 and 3, the fixed frame 5 includes a horizontal portion 51, a vertical portion 52 erected perpendicular to one end of the horizontal portion 51, and a second end of the horizontal portion 51. It comprises a downward surface 32 of the pressure receiving portion 3 formed, a protruding portion 53 formed closer to the other end than the center of the horizontal portion 51, and a hole 54 penetrating the shaft 9 formed in the protruding portion 53, For example,
The maximum width is 10.8 cm, the depth is 1.2 cm, and the maximum height is 1.65 cm. The horizontal part 51 is a downward facing surface 3
The upper surface of 2 is formed in a tapered shape. Further, a part of the horizontal portion 51 is inclined to avoid interference with the movable arm 7. The vertical portion 52 has a ball plunger 6
A female screw 55 that can be screwed with the screw 61 is threaded. The protrusion 53 has a rectangular shape having a height of about twice the height of the horizontal part 51 when viewed from the front. The projection 51 is retracted by about の of the depth of the projection 53. The use of such a large projection 53 minimizes rattling during rotation of the movable arm 7. In FIG. 1, reference numeral 55 denotes a bolt, which fixes the ball plunger 6 by tightening.

As shown in FIGS. 1 and 4, the movable arm 7 has a horizontal portion 71 and a ball receiving portion pierced at one end of the horizontal portion 71 which is swelled upward and downward to form a square in side view. 8, a pressure receiving surface 31 formed at the other end of the horizontal portion 71, and a projection 53 of the fixed frame 5 when supported by the fixed frame 5 via the shaft 9.
A projection 73 projecting downward at a position substantially equal to the above, a hole 74 penetrating the shaft 9 formed in the projection 73, and a projection of the fixed frame 5 when the fixed frame 5 is supported via the shaft 9. In order to avoid interference with the portion 53, a hole 75 wider than the protrusion 53 of the fixed frame 5 in a plan view is provided.

FIG. 6 schematically shows a hardness meter A for measuring the hardness of a tablet to be calibrated using the calibration device 1 for a hardness meter. The hardness meter A is provided below the sample table B, a pressing tip D for pressing the tablet C placed on the sample table B, a stepping motor E for lifting and lowering the pressing tip D, and a sample table B. And a recording device (not shown) for displaying and storing the breaking pressure of the tablet based on the electric signal output from the load cell F.

A method of calibrating the hardness meter A having such a configuration using the calibration device 1 for a hardness meter will be described below. The pressure required for separating the moderation mechanism 2 of the hardness meter calibration device 1 is adjusted in advance to a predetermined pressure, for example, 5 kg in terms of pressure of a pressure receiving portion.
This adjustment is performed by rotating the ball plunger 6,
When the adjustment is completed, the bolt 55 is tightened. In this adjustment, the distance between the pressure receiving portion 3 and the shaft 9, the moderation mechanism 2 and the shaft 9
Since the length is different, fine adjustment of the ball plunger 6 can be performed with high accuracy. As shown in FIG. 7, the sample is placed on the sample table B of the hardness meter A with the pressure receiving surface 31 of the pressure receiving unit 3 facing upward and the downward facing surface 32 facing downward. The stepping motor E is operated to apply pressure to the pressure receiving surface 31 of the pressure receiving section 3. The pressure is gradually increased by the stepping motor E. The pressure applied to the pressure receiving surface 31 is transmitted to the moderating mechanism 2 by the pressure transmitting mechanism 4, and when the transmitted pressure reaches a predetermined pressure, as shown in FIG. The engagement with the ball receiver 8 is released, and the ball receiver 8 separates from the ball 64. The movable arm 7 having the ball receiver 8 at one end rotates about the shaft 9 with respect to the fixed frame 5. Since the movable arm 7 has a pressure receiving surface 31 at the other end,
When the movable arm 7 rotates, the pressure receiving surface 31 rotates downward, and the pressure on the pressure receiving surface 31 disappears almost instantaneously. Therefore, if the pressure applied to the pressure receiving portion 3 when the ball 64 and the ball receiver 8 separate from each other is indicated by the hardness meter A to be 5 kg, the hardness meter A indicates the correct burst pressure. In this case, the calibration of the hardness meter A is completed, and if not instructed, the calibration is performed so that the instruction of the hardness meter A indicates 5 kg.

With such a configuration, the hardness meter calibrating device 1 detects the change in the pressure in the pressure receiving section 3 and applies pressure to a substance such as a tablet to reach a certain pressure. Since a state equivalent to the broken state can be reproduced, the pressure at the time of breaking can be obtained with high accuracy, that is, the calibration of the hardness meter A can be performed with high accuracy.

Further, since the ball plunger 6 that has been separated is one in which the urged ball 64 has detached from the ball receiver 8, the moderation mechanism 2 is reset by engaging the ball plunger 6 with the ball receiver again. it can. After the moderation mechanism 2 is adjusted as described above, it can be used repeatedly.

The moderating mechanism 2 can freely set the spring pressure by replacing the ball plunger 6, so that the hardness meter A to be calibrated can be calibrated over a wide range. Further, since the ball plunger 6 is screwed to the pressure transmitting mechanism 4, the predetermined pressure in the moderation mechanism 2 can be reduced by rotating the ball plunger 6 to change the screwing position in the pressure transmitting mechanism 4. Can be adjusted.

Since the pressure receiving portion 3 has the downwardly facing surface 32 formed flat, the seating when the pressure receiving portion 3 is mounted on the sample table B of the hardness meter A is good, and the pressure receiving surface 31 is curved upward. Since it is formed in a shape, pressure can be received by point contact.

The hardness meter calibration device 1 has a total length of 10.
The small size of 8 cm, height 1.65 cm and depth 1.2 cm makes it easy to carry and facilitates on-site calibration.

Next, another embodiment of the present invention will be described with reference to the drawings.

FIG. 9 is a principle diagram showing a calibration device 101 for a hardness tester. The calibration device 101 for a hardness tester has a moderation mechanism 102 that separates at a predetermined pressure at one end, and a pressure receiving portion 103 that receives pressure from outside is provided at the other end, and a pressure applied to the pressure receiving portion 103 is provided. To the moderation mechanism 102
And a pressure transmitting mechanism 104 is provided between both ends for almost instantaneously eliminating the pressure in the pressure receiving section 103 when the moderation mechanism 102 is separated.

The detent mechanism 102 includes a ball plunger 106 and a ball receiver 108 having the same structure as in the above embodiment.
And the ball plunger 106 is fixed frame 1
The ball receiver 108 is attached to one end of the movable arm 107.

The pressure receiving section 103 includes a pressure receiving surface 131 having a semicircular shape in front view for receiving pressure, and a downward surface 132 placed on the sample table B of the hardness meter A. The pressure receiving surface 131 is supported by the fixed frame 105 so as to be slidable up and down. The downward surface 132 is formed by the downward surface of the fixed frame 105 located below the pressure receiving surface 131.

The pressure transmitting mechanism 104 includes a cam surface 141 formed below the pressure receiving surface 131 and inclined at, for example, 45 degrees.
A movable arm 107 having a ball receiver 108 at one end and a roller 171 capable of rolling on the cam surface 141 at the other end; a movable arm 107 slidable left and right; And a fixed frame 105 that supports the 103 in a vertically slidable manner. The cam surface 141 is slidably supported in the up and down direction by the fixed frame 105, and can be moved to the left and right by the movable arm 107 via a roller 171. It is supported by.

In such a configuration, as shown in FIG. 10, when pressure is applied to the pressure receiving surface 131 by the pressure tip D, the downward pressure is changed to rightward pressure by the cam surface 141 and the roller 171. It is converted and transmitted to the moderating mechanism 102 via the movable arm 107. When the pressure reaches a predetermined value, the engagement between the ball plunger 106 of the moderation mechanism 102 and the ball receiver 108 is released, and the balls are separated. That is, the ball receiver 108 vigorously moves to the right. Accordingly, the movable arm 107 having the ball receiver 108 at one end also moves rightward. The rightward force is converted to a downward force by the cam surface 141 and the roller 171 that rolls on the cam surface 141, and the pressure is applied to the pressure receiving surface 131.
And the pressure receiving surface 131 moves downward, and the pressure receiving portion 1
The pressure at 03 disappears almost instantaneously. Therefore, as in the above-described embodiment, when a change in the pressure in the pressure receiving portion is viewed, a pressure is applied to a substance such as a tablet, and a state equivalent to a state destroyed by exceeding a certain pressure can be reproduced. The same effect as the above embodiment can be obtained.

The present invention is not limited to the embodiment described above. In addition, the configuration of each unit is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0032]

According to the present invention, as described in detail above, the resettable detent mechanism is separated by applying a predetermined pressure by the pressure transmitting mechanism, and the pressure transmitting mechanism substantially reduces the pressure in the pressure receiving portion. Since it disappears instantaneously, it is possible to easily reproduce the pressure change when the tablet or the like is broken. In addition, if the moderation mechanism is reset, it can be used again, and the running cost required for calibration can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing the front, side, and plane of an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a diagram showing a front surface and a plane of the fixed frame of the embodiment.

FIG. 4 is a diagram showing a front surface and a plane of the movable arm of the embodiment.

FIG. 5 is a sectional view showing a moderation mechanism of the embodiment.

FIG. 6 is a diagram schematically showing a hardness meter using the embodiment as a calibration device.

FIG. 7 is an operation explanatory view of the embodiment.

FIG. 8 is an operation explanatory view of the embodiment.

FIG. 9 is a principle view showing another embodiment of the present invention.

FIG. 10 is an operation explanatory view showing the present embodiment.

[Explanation of symbols]

 1, 101: Calibration device for hardness meter 2, 102: Moderation mechanism 3, 103: Pressure receiving part 4, 104: Pressure transmission mechanism 5, 105: Fixed frame 6, 106: Ball plunger 7, 107: Movable arm 8, 108 Ball receiver 9 ... shaft

Claims (2)

(57) [Claims] 1. A resettable moderation mechanism, which is separated by a predetermined pressure, is provided at one end, and a pressure receiving portion receiving external pressure is provided at the other end, and the pressure applied to the pressure receiving portion is reduced by the moderation. A calibration device for a hardness tester, wherein a pressure transmission mechanism is provided between both ends for transmitting the pressure to the mechanism and for eliminating the pressure in the pressure receiving portion almost instantaneously when the moderation mechanism separates. 2. A pressure transmitting mechanism comprising a fixed frame and a movable arm rotatably supported on the fixed frame via a shaft, wherein a moderation mechanism is attached to one end of the fixed frame. 2. A calibration device for a hardness tester according to claim 1, wherein the calibration device comprises a ball plunger and a ball receiver attached to one end of the movable arm and engageable with the ball plunger.