JPS6042571B2 - timer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a timer that can be set for a long time using a simple mechanism.

In the Sakura mechanical timer, after setting an arbitrary time, the movable member is moved in proportion to the passage of time, and when the movable member reaches the position corresponding to the set time, a switch etc. is activated to generate a signal as a timer. The moving action of the movable body is performed by circular motion or linear motion.

To get a timer with a long setting time, select "1 minute"
, "10 minutes", "1 hour", etc., are placed side by side on one axis, and when the lower drum that displays the unit time of "1 minute" rotates once, It was necessary to rotate the upper drum by one pitch, and then repeat this action between each drum to gradually rotate the upper drum. In other words, a long moving distance of the movable body is obtained by rotating many lower drums and carrying up, but this drum method requires a carry mechanism between each drum, making the mechanism complicated. There is an inconvenience that it becomes bulky as it becomes larger. Furthermore, if the movable body is moved linearly for a long time, the linear distance becomes very large, which is not practical.
On the other hand, if you try to obtain a timer with a long time setting by moving the movable body over a short distance, the speed of the movable body must be extremely slow, making it extremely difficult to accurately feed the body. This had the disadvantage that it required a reduction gear with a large ratio, making it expensive. An object of the present invention is to provide a new timer that uses an elastic body such as synthetic resin rubber and is capable of setting a long time even when a movable body moves over a short distance.

The present invention will be explained below with reference to illustrated embodiments.

In FIG. 1, an object 2 with a mass W is placed on a horizontal stationary member 1, and an object 5 with a mass W2 is moved by a string 4 through a pulley 3 that is mounted on the stationary member. When suspended, the vector diagram of the force acting on object 2 is the second
The result will be as shown in the figure.

That is, when force 6 of mass W acts on a stationary member, force 7 is a reaction force, equal in magnitude and opposite in direction, and the force due to mass W2 is represented by symbol 8. , the frictional force 9 at that time is represented by the symbol F, where μ indicates the friction coefficient.

The force 10 by which the object 2 is pulled to the right in FIG. 1 is represented by the symbol R.

According to the equation of motion, force is the product of mass and acceleration, so the object 2 moves under the acceleration α=R/m.

If we try to create a timer based on this relationship between motion and time, it will be difficult to create a long timer unless α is made extremely small and the speed is low. Therefore, the value of R in equation (3) needs to be made extremely small. For this purpose, in equation (2), W1×μ must be made extremely close to W2 within a range smaller than W2. However, in general, the value of the friction coefficient of objects has a fairly large fluctuation range, and even in the same combination of objects, it differs markedly depending on the contact area. Therefore, in equation (2), the value of W1 × p is used as the value of W2. As the distance is gradually brought closer, the friction coefficient μ
If there is a fluctuation in the value of , the movement of the movable object 2 may stop in some cases. In order to avoid this unstable region, if the mass W1 is made small, the acceleration will become large. You can't get it. The timer of the present invention, which eliminates this drawback, will be explained with reference to the figures starting from FIG. 3. In FIG. It has a ■-shaped shape when viewed from the side, and its press-contact portion causes elastic deformation on the surface of the substrate 13 and is slightly recessed.

The substrate 13 is made of a flexible elastic material such as synthetic resin rubber, and is fixed to an immovable member 14 such as a timer case so that such elastic deformation occurs. One end of a thread 16 is locked to an arm 15 fixed to a movable member, and after this thread 16 is hung on a pulley 17 mounted on a fixed member, a mass W2 is attached to the other end. A weight 18 serving as a driving source is locked. The direction of movement of the arm portion 15 (third direction)
A lever 22 of a switch 21 fixed to a stationary member 19 is arranged in the passage (right side in the figure), and when the movable member 11 moves to the right and the arm 15 presses the lever 22, the push button is pressed. 23 to activate the switch 21. The principle by which the contact portion between the leg portion 12 of the movable member 11 and the substrate 13 in FIG. 3 produces the low-speed movement necessary for the timer of the present invention will be explained with reference to FIG. 4 and subsequent figures.

4 and 6 are enlarged views of the contact portion, and for ease of explanation, the leg portion 12 in FIG.
The shape of the contact piece will be replaced with a cylindrical contact piece as shown in the figure. In FIG. 4, when a force W1 is applied vertically downward to the contact piece 31, a part of the contact piece 31 is pushed into the original surfaces 32 and 33 of the substrate 13 and A concave portion 34 is formed, and some portions form raised portions 35 and 36 to balance the force W1. The vector acting on this contact piece 31 is as shown in FIG.
, 38 and a reaction force 39 generated by compression of the substrate 13, the force W1 is balanced by the sum of the reaction force 39 and the like. Now, as shown in FIG. 3, when we apply a force W2 that acts on the movable body 11 in the lateral direction, its vector is as shown in FIG. It becomes like this.

The reaction force of this force 42 is the force 4 acting on the lower surface of the contact piece 31.
3 and forces 44, 45, etc. acting on both sides thereof. To explain this with reference to FIG. 6, the force 43 is a component force that is on the opposite side of the force 42 that mainly acts on the contact piece 31 and acts as a pressure, and the component force 45 is a component force that acts on the original surface 32 of the substrate 13, 33 to produce a raised portion 46,
Moreover, the density of the raised portion 46 is increased. The component force 44 acts to apply a tensile force to the part indicated by the reference numeral 47,
Therefore, the density of the portion 47 is lowered and a portion thereof forms a recessed portion. When the pressure contact portion of the contact piece 31 is in such a state, a creep phenomenon of the synthetic resin rubber constituting the substrate 13 occurs from the high-density raised portion 46 to the low-density portion 47, resulting in as contact piece 31
is moved in the direction of arrow 48. This creep phenomenon changes slowly over time, so
A displacement mechanism that utilizes this phenomenon can be used as a practical timer that operates over a short distance and for a long time. To further explain the above point, creep refers to the phenomenon in which strain increases over time when a load is applied to an object, and synthetic resins tend to creep more rapidly than metals. Resin rubber etc. have a large amount of creep. When the contact piece 31 performs the pressure contact action as shown in FIG.
Distortion that occurs on both sides of the contact piece 31, that is, the raised portion 35,
36 increases over time. At first, the amount of strain is large, but as time passes, the amount of strain decreases and eventually exhibits a phenomenon similar to saturation. That is, creep is a type of stress relaxation phenomenon. Next, if we further consider the creep phenomenon in the pressure welding state shown in FIG. , and the area on the left is generally under tension. For this reason, the area around the raised portion 46 has a high density, whereas the area 47 has a low density. And with the passage of time,
As shown by arrow 51, the movement of rubber molecules from areas of high density to areas of low density causes a stress relaxation effect. As a result, when the sum of the reaction forces 43, 44, and 45 becomes smaller, the change in the bulge 46 newly compressed by the resultant force 42 and the portion 47 that supports the component force by tension increases, As a result, the contact piece 31
move in the direction of And the creep phenomenon is
The movement of the movable body is relatively gradual with the passage of time, and especially compared to the movement due to the acceleration of α=R/m shown in equation (3) above, the movement effect due to the creep phenomenon is extremely gradual. Even if the amount of movement of 11 is within a small range of several centimeters to tens of centimeters, a movement with a long displacement time and a constant displacement speed can be obtained, and during the displacement, as shown in Fig. 3, By providing the switch 21, a time switch and various timers that can be set for a long time can be obtained. In FIG. 3, the movable body 11 is guided by an appropriate guide member so as not to rotate, and the base plate 13 is not necessarily linear, but is circular, such as a drum, to guide the movable body 1.
A similar effect can be obtained even if 1 is moved in a circular motion. According to the present invention, the substrate to which the movable body comes into pressure contact is made of synthetic resin rubber or the like, and the movable body can be moved very gently within a short distance by the creep phenomenon of strain that occurs before and after the pressure contact part. Therefore, it is possible to obtain a timer that can be set for a long time with a simple mechanism.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the frictional motion of an object on a plane used to explain the present invention in detail, FIG. 2 is a vector diagram acting on the object shown in FIG. 1, and FIG. FIG. 4 is a front view of a timer showing one embodiment of the present invention, and FIG. 6 is a vector diagram of the pressure contact action in the figure, FIG. 6 is a change diagram of the pressure contact action in FIG. 4, and FIG. 7 is a vector diagram of the same as above. 11...Movable body, 13...Substrate, 31...
...Contact l piece, 21...Switch.

Claims (1)

[Claims] 1. A substrate made of a flexible elastic material such as synthetic resin rubber, and a movable member that causes elastic deformation of the surface of the substrate by being brought into pressure contact with the substrate, and that is slidably provided in the surface direction of the substrate. , a drive source for moving the movable member, and a switch disposed within the locus of movement of the movable member, and the movable member is provided with a drive source that moves the movable member, and is provided with a switch disposed within the locus of movement of the movable member, and the movable member is provided with a drive source that moves the movable member by the movement action of strain that occurs in the direction of movement of the biting portion of the movable member into the substrate. The timer is characterized in that the movable member is moved at a constant low speed over time.