JPH0431557Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a zero point return mechanism for a zero return totalizer using a heart cam.

[Conventional technology]

Generally, by manually rotating the zero return knob, the rotation is transmitted to the totalizer via a transmission mechanism, and the rotating drum of the totalizer is returned to its original position. A totalizer with a zero return function is already known, in which a pointer rotating integrally with a heart cam is returned to a zero point position on a scale plate by being locked in a recessed portion.
3A and 3B show the first conventional example, and FIGS. 4A and 4B show the second conventional example.

In the first conventional example, the heart cam 1 that can engage with the zero point securing lever 4 to maintain the zero point position is provided with a bearing cylinder part 13, and the pointer 5 is fixed to this bearing cylinder part 13. The pointer shaft 7 is inserted, a spring stopper 10 is planted on the inner flat surface of the heart cam 1, a notch 14 is provided in a part of the bearing cylinder part 13 of the heart cam 1, and the spring 12 is hung on the spring stopper 10 to secure the pointer shaft. 7 is sandwiched between the tips of the springs 12, and the heart cam 1 and the pointer shaft 7 are locked and fixed and rotated.

Next, in the second conventional example, the spring stopper 11 is installed on the outside of the heart cam 1, so that machining of the notch in the bearing cylinder portion 13 of the heart cam 1 is not required.

[Problem that the invention attempts to solve]

However, in such conventional zero point return mechanisms, both the first and second conventional examples have a spring stopper 1.
0 and 11 are planted outside the heart cam 1, it is difficult to process the notch 14 in the first conventional example. The problem was that it became weak.

Next, in the second conventional example, when the spring stopper 11 is installed on the outside of the heart cam 1, the bearing cylinder portion 13
Although it is no longer necessary to cut out the parts, there is a problem in that the overall structure becomes longer horizontally, which goes against the trend of making the equipment more compact.

This idea was devised by focusing on these problems, and by mounting the spring inside the heart cam, there is no need to provide a notch in the bearing cylinder of the heart cam, and the overall structure can be made compact. The aim is to solve the above problems.

[Means for solving problems]

In this invention, a spring is attached to a recess made in the flat part of a heart cam in a totalizer with a zero return function.

〔Example〕

Figure 1 shows an embodiment of this invention, Figure 1A is a diagram of the relationship between the heart cam and the zero point securing lever when securing the zero point position, Figure 1B is a side sectional view, and Figure 1C is the zero return operation. FIG. 1D is a diagram showing the relationship between the heart cam and the zero point securing lever outside of the zero return operation.

A bearing cylinder part 13 is extended to the heart cam 1 which engages with the zero point securing lever 4 to maintain the zero point position, a pointer 5 is fixed to this bearing cylinder part 13, and a pointer shaft 7 is attached to the bearing cylinder part 13. A ring-shaped spring 3 is inserted into a recess 2 made in the flat surface of the heart cam 1, and the tension of the spring 3 locks and fixes the pointer shaft. During integration, the ring-shaped spring 3 is frictionally transmitted by the spring tension to the outer circumferential groove of the pointer shaft 7, causing the pointer shaft 7 to rotate together with the heart cam 1. At the same time, a transmission gear 8 fixed to the pointer shaft 7 rotates integrally with the pointer shaft 7. The rotation is transmitted to a rotating drum (not shown) of a totalizer (not shown) via a transmission mechanism (not shown). During the zero return operation, if you manually operate the zero return knob (not shown) and press the tip of the zero point securing lever 4 against the outer periphery of the heart cam 1, the heart cam 1 will return to the zero point on the outer periphery as shown in Fig. 1C. It rotates while contacting the tip of the securing lever 4, and is secured at the zero point at the position shown in FIG. 1A, and the rotating drum of the totalizer is also returned to the zero point. After the zero point is secured, the zero return operation is stopped, so the zero point securing lever 4 is removed from the outer periphery of the heart cam 1, as shown in FIG. 1D.

[Other Examples]

FIG. 2 shows another embodiment of this invention.

During the zero return operation, as mentioned above, the tip of the zero point securing lever 4 contacts the outer periphery of the heart cam 1 and slides, so sufficient consideration must be given to the surface roughness and material of both to prevent wear on the contact surfaces. It is.

Also, depending on the adjustment position, a dead center may easily occur. In this embodiment, a ball bearing is used at the tip of the zero point securing lever, and since rolling contact occurs, the above-mentioned problem can be solved.

[Effect of idea]

This idea has the effect that the spring is installed in a recess drilled into the flat surface of the heart cam, making the overall structure more compact, and since there is no need to drill into the bearing tube of the heart cam, the bearing tube becomes stronger. .

In addition to the above-mentioned effects of this invention, according to the second embodiment, by providing a ball bearing at the tip of the zero point securing lever, there is an effect that wear of the heart cam and the zero point securing lever can be prevented.

[Brief explanation of the drawing]

Figure 1 shows an example of this invention. Figure 1A is a diagram of the relationship between the heart cam and the zero point securing lever when securing the zero point position, Figure 1B is a side sectional view, and Figure 1C is a diagram showing the relationship between the heart cam and the zero point securing lever when the zero point position is being secured. FIG. 1D is a diagram showing the relationship between the heart cam and the zero point securing lever. FIG. 1D is a diagram showing the relationship between the heart cam and the zero point securing lever outside of the zero return operation. FIG. , Figure 4A is a diagram of the relationship between the heart cam and the zero point securing lever when securing the zero point,
FIGS. 3B and 4B are side views. Note that the same reference numerals in each figure indicate the same or corresponding parts. 1...heart cam, 2...recess, 3...spring,
4... Zero point securing lever, 5... Pointer, 9... Ball bearing, 13... Bearing cylinder.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a totalizer with zero return, a bearing tube is provided on the heart cam that can engage with the zero point securing lever to maintain the zero point position, and a pointer is fixed to this bearing tube, and A heart cam type zero point, characterized in that a pointer shaft is inserted into the bearing cylinder portion, a spring is attached to a recess made in a flat surface of the heart cam, and the pointer shaft is locked and fixed by the tension of the spring. Return device. (2) The heart cam type zero point return device according to claim 1, which is a utility model registration, characterized in that a ball bearing is provided at the tip of the zero point securing lever that engages with the heart cam.