JPH1177853A - Knob member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use with high durability a knob member even when the member is used under the environment around a kitchen. SOLUTION: A fitting section 7 for fitting an operation member 2, which is provided on a separate section, is formed in the bonded state on an operation member setting section 3 formed of amorphous resin, and a knob section 4 used for the operation of the transmitting force to the operation member 2 in the state of fitting the operation member 2 on the fitting section 7 is formed. An annular channel 10 encircling a setting section 7a is formed in a wall thickness formed between a contact face 7a being in contact with the operation member 2 on the fitting section 7 and an opposite face 7b facing the contact face 7a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an operating member mounting portion made of non-crystalline resin, which is provided with a fitting portion capable of tightly fitting an operating member provided on another object in a tight state. A knob member having a knob portion for performing an operation of transmitting a force to the operation member in a state where the operation member is fitted,
For example, stove knobs, slide knobs, operating levers, which are subjected to stress in applications where a surfactant may adhere, such as kitchenware, bathware, toilet articles, toilet articles, and the like.
The present invention relates generally to resin molded products such as switches.

[0002]

2. Description of the Related Art Conventionally, a knob member of this type is formed of a non-crystalline resin such as ABS in order to improve dimensional accuracy in molding the operation member mounting portion. The force is easily transmitted between the operating member mounting portion and the connector, for example, in such a manner as to be easily fitted in a close contact state. In the resin molded product, a portion that transmits force with the operating member is easily exposed to an environment maintained in a stressed state (a portion that receives this stress is referred to as a stress receiving portion). Therefore, from the viewpoint of securing dimensional accuracy, it is merely formed by using an amorphous resin so as to conform to the shape of the operation member.

[0003]

At this time, the stress receiving portion receives a direct force in a direction in which it comes into contact with a surface of the stress receiving portion at a portion which normally comes into contact with the operating member. In many cases, a portion away from the surface receives a surface tensile stress (hereinafter, simply referred to as a surface stress) in a direction along the surface. Incidentally, resin molded products are exposed to various use environments. Among them, for example,
It can be said that a resin molded product such as a knob member used for a gas appliance or the like used around a kitchen is in an environment where various kinds of deposits such as a detergent easily adhere. However, conventional resin molded products exposed to such an environment are known to have particularly low durability, and it has been desired to investigate the cause and take countermeasures. Specifically, it is known that resin molded products used in such an environment are not heavily used than those used in other environments, but are liable to crack.

Accordingly, it is an object of the present invention to provide a resin molded product which can be used with high durability even when used in an environment such as around a kitchen in view of the above-mentioned situation.

[0005]

Means for Solving the Problems The present inventors have compared the use environments in which the above-mentioned differences in durability occur, and found that in the environment around the kitchen, various kinds of deposits were found particularly on resin molded products. Attention was paid to the fact that there is a difference from other environments in that it easily adheres. Then, as a result of intensive studies to avoid the influence of the deposits, among the above-mentioned deposits, in particular, due to a surfactant contained in a detergent or the like, the durability of the resin molded product may be significantly reduced. , And various findings on the adverse effects of such detergents were obtained. The present invention has been made based on these findings, and the characteristic configuration of the resin molded product of the present invention is that an operating member provided on another object is closely attached to an operating member mounting portion made of an amorphous resin. A fitting portion that can be fitted is provided, and in a state where the operating member is fitted to the fitting portion, a knob portion that performs an operation of transmitting a force to the operating member is formed, and In the point that an annular groove surrounding the fitting portion is provided within the thickness between the contact surface that contacts the operation member and the opposing surface that faces the contact surface, more specifically, The rotating shaft mounting portion made of an amorphous resin is provided with a cylindrical fitting portion capable of fitting the rotating shaft in a tight state, and the rotating shaft is fitted to the fitting portion while the rotating shaft is fitted. Forming a knob portion for performing a rotating operation to transmit a rotating force to the rotating shaft in the fitting portion. An annular groove surrounding the fitting portion may be provided within the thickness between the contact surface to be contacted and the opposing surface opposite to the contact surface, and the rotary shaft attachment portion and the knob portion may be provided. Is desirably integrally molded. In addition, it is sufficient that a protrusion protruding outward is provided on the facing surface of the rotating shaft mounting portion, and when the rotating shaft is fitted to the fitting portion, it can be pressed against the rotating shaft. A simple spring member may be interposed in the fitting portion.

[Effects] According to the various findings of the present inventors, if a surfactant or the like continues to adhere to a portion of a resin molded product where a surface stress is continuously applied, the surfactant or the like becomes It is considered that the composition has some adverse effect on the composition by permeating into the inside of the resin molded product or eluting the components inside. In other words, stress concentration points
It can be said that the strength of the resin molded product is liable to be greatly reduced (deteriorated) when the adhesion position of the surfactant or the like coincides, and the contact surface and the facing surface are separated by the annular groove. In this case, the surface stress in the stress receiving portion reaches only the annular groove portion, and no direct surface stress is generated on the facing surface, so that a situation in which the surface stress is continuously applied can be avoided. As a result, even if a surfactant or the like adheres to the resin molded product, deterioration due to the surfactant can be prevented, and the inherent performance of the knob member can be exhibited.
Here, since the amorphous resin portion between the annular groove and the facing surface is not directly subjected to surface stress, even if it is deteriorated by the surfactant, it does not easily become deteriorated rapidly. The non-crystalline resin portion only needs to have the material characteristics of a normal non-crystalline resin, and a sufficient function can be exhibited only by providing a simple structure for forming an annular groove.

More specifically, a cylindrical fitting portion is provided on the rotating shaft mounting portion made of an amorphous resin so that the rotating shaft can be fitted in a tight state, and the rotating shaft is fitted into the fitting portion. In the combined state, a knob member that forms a knob portion for performing a rotating operation to transmit a rotating force to the rotating shaft is specifically present in many environments such as around a kitchen, and Because it is a member that rotates, it is easy to cut off the transmission of stress and prevent surface stress from occurring,
A simple process of simply providing an annular groove surrounding the fitting portion works effectively. In addition, when the rotary shaft mounting portion and the knob portion are integrally molded, the moldability is good, and the portion that transmits stress between members is minimized, the surface stress generating portion is reduced, and the quality is improved. It is useful for stability. Further, it is preferable because the handleability as a molded product is excellent. Also,
If the facing surface of the rotating shaft mounting portion is provided with a protruding portion protruding outward, a situation in which a surfactant or the like attached to the facing surface runs down the surface and enters the annular groove portion. Therefore, it is possible to more effectively prevent a situation in which the knob is deteriorated by a surfactant or the like that has entered the annular groove portion and the durability is reduced. Also,
When the rotating shaft is fitted to the fitting portion, if a spring member interposed portion for interposing a spring member so as to be able to press against the rotating shaft is provided in the fitting portion, Since it becomes possible to make the knob member more closely contact with the knob member, the transmission of force between the rotary shaft and the knob member is effectively performed, and an abnormal stress load state is unlikely to occur.
This is preferable in terms of improving the durability of the knob member.

The base material of the knob member is preferably made of polystyrene resin such as ABS, polyphenylene ether, polysulfone, polyethersulfone, polycarbonate, polyarylate, polyetherimide in consideration of dimensional stability at the time of molding. And non-crystalline resins such as polyimide and polyamide imide.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a resin molded product of the present invention will be described below with reference to the drawings, taking a knob for a stove as an example. (Embodiment 1) As shown in FIGS. 1 to 3, a knob 1 for a stove is provided with a rotating shaft mounting portion 3 which can be fitted in close contact with a rotating shaft 2 for operating a spark plug of the stove and the rotating shaft 2 AB together with a knob 4 and a base 5 for rotating the
It is integrally formed from S resin. The base 5 is formed in a circular shape in plan view to cover the space between the stove body 6 and the rotating shaft 2 and has a plate-shaped knob 4 protruding from the surface thereof. The rotating shaft mounting portion 3 is formed in a cylindrical shape on the rear surface side of the base portion 5, and has a prismatic fitting portion 7 for fitting the rotating shaft 2 in a close contact state, and the fitting portion 7 is provided on the fitting portion 7. A spring member mounting portion 9 for interposing a spring member 8 so as to be able to press against the rotary shaft 2 when the rotary shaft 2 is fitted is provided. In the stove knob 1, the rotating shaft mounting portion 3 corresponds to a portion to receive a stress, so that the contact surface 7 of the fitting portion 7 which contacts the rotating shaft 2 is provided.
An annular groove 10 surrounding the fitting portion 7 is provided in the thickness between the contact surface 7a and the facing surface 7b facing the contact surface 7a. Although a surface stress is generated in the vicinity of the arrow portion in FIG. 2, no stress is transmitted to a portion outside the annular groove.

Comparative Example A stove knob 1 having no annular groove 10 was manufactured for comparison.

The stove knob 1 was forcibly caused to generate a stress by the rotating shaft 2, and a nonionic surfactant was adhered to the facing surface 7b. In the case of the one having been left for 24 hours, cracks occurred at the surface stress generating portion (near the facing surface 7b), whereas in the case of the embodiment, no cracks occurred and the durability by the surfactant was high. It is considered that no decrease has been observed.

[0012]

In order to demonstrate the present invention, various ABSs will be described below.
The resistance of the resin molded article to the detergent was examined by the so-called quarter ellipse method.

(1/4 Ellipse Method) As shown in FIG. 5, one end of a plate-shaped resin molded product sample is attached to a mounting portion 101 on a sample attachment jig 100 having an elliptical outer surface. The other end is fixed to the fixing portion 102 so as to be deformed into a shape along the outer surface of the one-side mounting jig 100, a state where surface stress is generated is realized, and a detergent or the like is brought into contact. The critical strain was examined under the conditions of a temperature of 23 ° C. and a humidity of 50%. At this time, since the outer surface of the sample piece mounting jig 100 is represented by a quadratic curve represented by Equation 1 (1) when viewed in a longitudinal side view, the x-axis length of the elliptical portion is calculated from this equation. Where a is (here 127) y-axis length is b and (here 38.1) the thickness of the test piece is t, and the distance in the x-axis direction to the point where cracks and crazes occur at the minimum strain is When X is set, the critical strain ε is given by Expression 1 (2).

[0014]

(Equation 1)

The results are as shown in Table 1, and it was found that when the nonionic detergent was attached, the critical strain was particularly greatly reduced. In addition, when tests were conducted using various chemicals in addition to detergents, some bathing agents and the like decreased the durability of the resin, and it is considered that a surfactant was involved. In addition, it has been suggested that oils, seasonings, and the like are also involved in the deterioration of physical properties. According to the structure of the present invention, physical properties are not limited to be reduced by not only surfactants but also various chemicals. It turns out that it is also useful.

[0016]

[Table 1]

[Alternative Embodiment] As the operation member mounting portion,
The present invention is not limited to the rotary shaft mounting portion, but may be a slide knob mounting portion or a push lever mounting portion. These are collectively referred to as an operation member mounting portion. Further, as shown in FIG. 4, an outwardly protruding projection 11 may be provided on the facing surface of the rotating shaft mounting portion, and in this case, the rotating shaft mounting portion 3 may be provided. Detergent etc. adhered to the surface,
It is preferable because it can be prevented from reaching the surface stress generation site. The protruding portion 11 is preferably provided over the entire outer surface of the facing surface 7b, and is preferably provided near the end of the rotating shaft mounting portion 3 on the side of the rotating shaft fitting entrance. Further, the contact surface 7a side and the opposing surface 7b side of the operation part agent attaching portion may be formed in such a shape that the contact surface side retreats to the back, so that the detergent or the like adhered to the rotating shaft attaching portion 3 can be formed. However, it can be prevented from traveling along the surface and reaching the surface stress generation site.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stove.

FIG. 2 is a perspective view of a stove knob.

FIG. 3 is a vertical side view of a stove knob.

FIG. 4 is a longitudinal sectional side view of a stove knob according to another embodiment.

FIG. 5 is a perspective view of a sample piece mounting jig.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resin molded product 2 Rotation shaft 3 Rotation shaft attachment part 4 Knob part 5 Base part 7 Fitting part 10 Annular groove part

Claims (5)

[Claims] An operating member mounting portion made of a non-crystalline resin is provided with a fitting portion capable of tightly fitting an operating member provided on another object in a close state, and the operating member is fitted to the fitting portion. A knob for performing an operation of transmitting a force to the operating member in a state in which the operating member is in contact with the operating member. A knob member provided with an annular groove surrounding the fitting portion within a thickness between the facing surface and the opposite surface. 2. A rotary shaft mounting portion made of an amorphous resin,
A rotary fitting is provided in which a rotary fitting is provided such that the rotary shaft can be fitted in a close contact state and the rotary shaft is fitted in the fitting portion. A knob member forming a knob portion, wherein a contact surface of the fitting portion, which is in contact with the rotating shaft,
A knob member provided with an annular groove surrounding the fitting portion in a thickness between the contact surface and the opposing surface. 3. The knob member according to claim 2, wherein said rotary shaft mounting portion and said knob portion are integrally formed. 4. The knob member according to claim 2, wherein an outwardly protruding projection is provided on the facing surface of the rotating shaft mounting portion. 5. The fitting portion according to claim 2, wherein a spring member that can be pressed against the rotating shaft when the rotating shaft is fitted to the fitting portion is interposed in the fitting portion. The knob member according to claim 1.