JPH0723239U - Balance with windshield - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a balance with a draft shield that eliminates the risk that a user of a balance may pinch a finger or an object to the door without noticing that the door is open when calibrating the sensitivity. [Configuration] Opening / closing drive device for driving the windshield door, a door position sensor for detecting the open / closed state of the windshield door, an alarm device for issuing a warning when the windshield door is open and a sensitivity calibration command is issued, and the windshield door is closed. A timer for adjusting the timing is provided, and a warning is given if the door is open when starting the sensitivity calibration, and the door is closed after a predetermined time has elapsed to perform the sensitivity calibration.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a balance with a windshield.

[0002]

[Prior art]

 Generally, in a high-precision balance, a windshield that surrounds the weighing chamber in which the weighing pan is installed is provided in order to prevent fluctuations in the weighing value caused by the wind acting on the weighing pan. In addition, it is equipped with a function that allows the operator to calibrate the sensitivity at any time in order to make accurate measurements, and when the operator issues a sensitivity calibration command as necessary, the sensitivity calibration is automatically performed by adding or removing the built-in weight. It can be done.

Conventionally, in such a balance with a windshield, if a sensitivity calibration command is issued, in order to perform accurate sensitivity calibration, the sensitivity cannot be calibrated unless the door of the windshield is closed, or If the balance has an automatic door opening / closing mechanism, the door is forcibly closed to calibrate the sensitivity.

[0004]

[Problems to be solved by the device]

 With the conventional balance with an automatic door, when the sensitivity is calibrated, the balance user suddenly closes the door when the user does not notice that the door is open and tries to calibrate the sensitivity. , There was a very high risk of catching fingers or objects on the door, which caused the balance to malfunction. In addition, the automatic sensitivity calibration function does not make any sense for balances that do not perform sensitivity calibration when the door is open.

The present invention has been made in view of the above problems, and an object thereof is to safely and automatically calibrate the sensitivity when the sensitivity of the balance is corrected.

[0006]

[Means for Solving the Problems]

 The present invention adopts the following configuration in order to achieve such an object. That is, the balance according to the present invention is a balance with a windshield in which a weighing chamber having a weighing pan is covered with a windshield, a windshield door that opens and closes a working opening, an opening / closing drive device that drives the windshield door, and a windshield door. A door position sensor that detects the open / closed state of the vehicle, an adder / remover that removes the built-in weight that serves as the reference load during sensitivity calibration from the balance mechanism, and a warning that issues a warning when the windshield door is open and a sensitivity calibration command is issued. Equipped with a timer, a timer that adjusts the closing time of the windshield door, and an open / close determination means that determines the open / closed state of the door based on the signal from the position sensor.When the sensitivity calibration is started, a warning is issued if the door is open, The feature is that the door is closed after a lapse of a predetermined time to perform sensitivity calibration.

Hereinafter, the operation of the balance having this structure will be described.

[0008]

[Action]

 In the balance of the present invention, when the sensitivity calibration command is issued, the door position sensor detects whether or not the windshield door is open. If the draft shield door is closed, start sensitivity calibration immediately. When the windshield door is open, an alarm is issued to notify the measurer. Then, the waiting time preset in the timer is measured, and after the waiting time elapses, the windshield door opening / closing drive device is driven to close the windshield door, and then the sensitivity calibration is started. Therefore, even if a sensitivity calibration command is issued with the windshield door open, the operator will be alerted to the fact that the door is open, so it is not possible to accidentally catch a hand or DUT in the windshield door. Absent.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a balance showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a main part thereof. In this embodiment, the weighing pan 1 is installed in the weighing chamber 2, the load of the object to be measured placed on the weighing pan 1 is transmitted to a balance mechanism (not shown), and the load sensor engaged with the balance mechanism loads the load. Is measured. A built-in weight 4 is arranged in the housing 3 below the weighing pan 1, and the built-in weight 4 can be added to and removed from the balance mechanism by the addition / removal device 5.

The lower surface and the rear surface of the weighing chamber 2 are surrounded by the wall surface of the housing 3, the front surface is surrounded by the fixed windshield 6, and the left and right side surfaces and the upper surface are surrounded by the windshield door 7. When the windshield door 7 is closed, the weighing chamber 2 is closed. Is isolated from the outside so that it is not affected by the wind. An opening / closing drive device 8 is provided in the housing 3 to open / close the windshield door 7. The opening / closing drive device 8 is opened / closed by transmitting a rotational force from a motor (not shown) to a roller under the windshield door 7 by a belt mechanism. A position sensor 9 is installed in the housing 3 below the windshield door 7 to detect whether the windshield door 7 is in the closed position or the open position. Further, an alarm device 10 and a timer 11 are provided in the housing 3, and when an alarm issuance signal is received, an alarm is issued to the measurer for the time set by the timer.

A microcomputer 20 having a CPU, a ROM and a RAM for controlling and operating the balance is connected to each of the above devices. A keyboard (including the sensitivity calibration command switch 21) as an input / output device and a display are connected to the microcomputer 20.

Next, the operation of this balance will be described using a flowchart showing a program written in the microcomputer 20. FIG. 3 is a flow chart showing a program written in the ROM in the microcomputer 20 of the balance of this embodiment.

In this program, when the sensitivity calibration command switch 21 is pressed (ST1), the position sensor 9 determines whether the windshield door 7 is open (ST2). In this embodiment, the position sensor 9 is of an optical type and has a side for detecting the closed position and a side for detecting the open position, and outputs a signal when the windshield door is directly above each position sensor. To do. This signal is used to determine whether the door is open. When the position sensor 9 determines that the windshield door 7 is closed, the sensitivity calibration starts immediately (ST9). When the position sensor 9 determines that the windshield door 7 is open, the alarm device 10 issues an alarm notifying that the windshield door 7 is open (ST3). This allows the measurer to know that the windshield door is open and will soon recognize that the windshield door will automatically close. Then, the timer for setting the alarm notification time is reset (ST4), and the counting of the waiting time t previously set in the timer is started (ST5). The alarm continues to sound while the timer is counting, and eventually the set waiting time ends (ST6), the alarm stops (ST7), and the opening / closing drive device 8 operates to close the windshield door 7 (ST8). . Then, the built-in weight adding / removing device 5 operates to place the built-in weight 4 on the balance mechanism, and the impression calibration is performed (ST9).

In this embodiment, the sensitivity calibration command is manually issued. However, the present invention is not limited to this, and for example, a temperature change at a place where the balance mechanism is located is detected and a temperature above a predetermined temperature range is detected. A sensitivity calibration command may be automatically issued when there is a change. In this case also, the same operation is performed if the windshield door 7 is open.

[0015]

[Effect of device]

 According to the balance of the present invention, the sensitivity can be accurately calibrated because the door can be automatically closed even if the measurer issues a sensitivity calibration command while the windshield door is open. In addition, since the alarm is activated before the windshield door is closed, there is no danger of accidentally pinching a finger or DUT by the windshield door.

[Brief description of drawings]

FIG. 1 is a perspective view of a balance which is an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a balance which is an embodiment of the present invention.

FIG. 3 is a flowchart showing a program written in a microcomputer of a balance which is an embodiment of the present invention.

[Explanation of symbols]

 1: Weighing pan 2: Weighing chamber 4: Built-in weight 5: Addition / removal device 7: Windshield door 8: Open / close drive device 9: Position sensor 10: Alarm device 20: Microcomputer

Claims (1)

[Scope of utility model registration request] 1. A balance with a draft shield in which a weighing chamber having a weighing pan is covered with a draft shield, and a draft shield door for opening and closing an opening for working, an opening / closing drive device for driving the draft shield door, and an open / closed state of the draft shield door. Door position sensor to detect, adder / remove device to add / remove the built-in weight, which becomes the reference load at the time of sensitivity calibration, to the balance mechanism, an alarm device that issues a warning when the windshield door is open and there is a sensitivity calibration command, and the windshield door is closed. It is equipped with a timer that adjusts the timing and open / close determination means that determines the open / closed state of the door based on the signal from the position sensor.At the start of sensitivity calibration, a warning is issued if the door is open, and the door is opened after a predetermined time has elapsed. A balance with a draft shield, which is characterized in that the sensitivity is calibrated by closing it.