JPH0313636Y2 - - Google Patents

Description

[Detailed Description of the Invention] The mounting structure of the coil spring of the present invention will be explained according to the following items.

A. Industrial field of application B. Overview of the idea C. Prior art C-1 General background C-2 First example of conventional coil spring mounting structure [Figure 4] C-3 First example of conventional coil spring mounting structure 2 Examples [Figure 5] D Problem to be solved by the invention E Means for solving the problem F Example a Drive gear [Figures 1 and 3] b Friction wheel [Figures 1 to 3 ] c Connection between driving gear and friction wheel [Figure 1] d Driven gear [Figures 1 to 3] e Connection between driven gear, drive gear and friction wheel [Figure 1] f Cap body [Figure 1] 1 to 3] g Idler [Fig. 1 to 3] h Coil spring [Fig. 1 to 3] i Operation G Effect of the invention (A Industrial application field) The present invention is a novel coil Regarding spring mounting structure. Specifically, for example, in a slip mechanism using a coil spring, a coil is placed between each contact surface of two members whose spring contact surfaces are positioned to face each other, and at least one of which is rotated or rotated. This relates to a mounting structure for a coil spring in a mechanism that requires the spring to be placed in a state where the spring is compressed by a predetermined amount. It is an object of the present invention to provide a novel mounting structure for a coil spring that prevents the so-called stuck phenomenon or locking phenomenon of the spring from occurring by supporting it on one side of the member.

(B. Summary of the invention) The mounting structure of the coil spring of the present invention is arranged between each contact surface of two members in which the spring contact surfaces are positioned to face each other and at least one of which is rotated or rotated. In a coil spring mounting structure for a mechanism that requires a coil spring to be compressed by a predetermined amount and placed in a state where the ring at the contact end is in contact with the contact surface, both ends of the coil spring are attached to the two members. By supporting one of the two, malfunctions due to the so-called stuck phenomenon of the spring are prevented from occurring.

(C. Prior Art) C-1 General Background For example, when a load exceeding a predetermined torque is applied to the idler device, reel stand, or transmission gear block of the drive system that rotates the reel stand in a tape recorder, It is necessary to prevent the driving-side member and the driven-side member provided thereon from slipping against each other, thereby changing the running speed of the magnetic tape or stopping the movement of the member to be operated. .

For this reason, these reel stands and transmission gear blocks usually have a slip mechanism (such a mechanism and a "friction mechanism" or (Sometimes referred to as a "limiter mechanism.") is provided.

By the way, coil springs, plate springs, felts, magnets, etc. are used as frictional contact members in such slip mechanisms, and among these, coil springs are relatively often used.

C-2 First example of conventional coil spring mounting structure [FIG. 4] FIG. 4 shows an example of a conventional coil spring mounting structure in an idler device of a tape recorder.

In the drawings, reference numeral "a" denotes a support shaft erected on a chassis (not shown), and an annular groove "b" is formed in the upper end of the support shaft. Reference numeral c denotes a drive body formed in a substantially disk shape that is rotated by a drive source (not shown), and has an insertion hole d formed in its axial center. e is an idler arm, and an insertion hole f is formed at its base end. g is a coil spring, h
is a washer.

The support shaft a is sequentially inserted into the washer h, the coil spring g, the insertion hole f of the idler arm e, and the insertion hole d of the driver c, and is positioned so as to protrude upward from the insertion hole d of the driver c. A retaining washer (not shown) is engaged with the groove b of the support shaft a, so that the drive body c and the idler arm e are brought into pressure contact with each other by the elastic force of the coil spring g. It will be done.

When the drive body c is rotated, the rotational force is transmitted to the idler arm e by the friction generated at the contact portion between the drive body c and the idler arm e. A rotational force in a predetermined rotational direction is applied.

Note that one end of the coil spring g is in contact with the lower surface of the idler arm e, and the other end is in contact with the upper surface of the washer h. (C-3 Second example of conventional coil spring mounting structure [ Fig. 5] Fig. 5 shows another example of a conventional coil spring mounting structure in an idler device of a tape recorder.The difference between the one shown in Fig. 5 and the one shown in Fig. 4 is that the coil spring The only difference is that the lower end is supported by a spring receiver arm that rotates integrally with the idler arm, so only the different parts will be explained, and the same parts will be explained in the fourth section.
Explanation will be omitted by assigning the same reference numerals as those used in the figures.

In the figure, i is a substantially slit-shaped notch formed at the rotating end of the idler arm e. Also, j
is a spring receiving arm, and an insertion hole k is formed at its base end, and an engagement pin l is formed from its rotating end.
has been erected. Then, the support shaft a of the spring receiving arm j is inserted into the insertion hole k thereof, and the engagement pin l thereof is engaged with the notch i formed in the idler arm e, and the coil spring g is connected to the idler arm e and the spring receiving arm j. It is fitted onto the support shaft a between the support arm j and the support arm j.

As mentioned above, when the drive body c is rotated, its rotational force is transmitted to the idler arm e, and the engagement pin l erected from the spring receiving arm j is connected to the idler arm e. Since it is engaged with the notch i of the idler arm e
It will be rotated as one unit. Therefore, the coil spring g is rotated integrally with the idler arm e and the spring receiver arm j.

(Problems to be solved by the invention) Each of the coil spring mounting structures shown in FIGS. 4 and 5 has a problem in that a washer h and a spring receiving arm j are required.

That is, in the one shown in Fig. 4, if the washer h
If there was no such thing, the coil spring g would be compressed between two members that do not rotate integrally, namely the idler arm e and the lower end boss m of the support shaft a, so each contact between A slip will occur between the end ring and the member with which it comes into contact. In this case, since one end of the coil spring g is in contact with the lower surface of the idler arm e, the outer peripheral edge of the one end surface of the coil spring, that is, the edge portion is approximately perpendicular to the lower surface of the idler arm e. Since it is being contacted from such a direction, it is possible that
The edge of the coil spring g may get stuck on the bottom surface of the idler arm e. Similarly, since the other end of the coil spring g is in contact with the upper surface of the boss m, the edge of the other end of the coil spring g may bite onto the upper surface of the boss m.

In this way, if the coil spring g is stuck to the idler arm e or the boss m, the coil spring g will be twisted or the winding will spread out, causing significant fatigue to the coil spring g. At the same time, in extreme cases, the idler arm e may be locked.

Furthermore, if there were no spring receiving arm j in the one shown in FIG. There is an inconvenience that it may get stuck.

Therefore, the above-mentioned inconvenience is solved by providing a washer h and a spring receiving arm j, but this requires extra members, that is, a washer h and a spring receiving arm j, which reduces the number of parts. As the number of parts increases and the shape becomes larger, other problems arise, such as a decrease in the rotational torque of the driving body c.

(E. Means for Solving Problems) Therefore, in order to solve the above-mentioned problems, the mounting structure of the coil spring of the present invention is such that both ends of the coil spring are attached to one side of two members facing each other with the coil spring in between. It was designed to support the

Therefore, according to the present invention, since the edge portion of the end face of the coil spring does not come into contact with the spring contact surface of the member that is relatively rotated or rotated, the coil spring does not bite on the member. , the contact state between the ring at the contact end of the coil spring and the spring contact surface of the member is not impaired in any way.

(F. Example) Below, details of the mounting structure of the coil spring of the present invention will be explained according to the example shown in the attached drawings. still,
The embodiment shown in the drawings is an application of the present invention to a structure for mounting a coil spring in a transmission gear block of a tape recorder.

1 in the figure is a transmission gear block to which the present invention is applied.

(a Drive gear) [Fig. 1, Fig. 3] 2 is a drive gear.

The drive gear 2 includes a disk portion 3, a substantially cylindrical boss portion 4 integrally formed at the center of the disk portion 3 so as to penetrate the disk portion 3 in the thickness direction, and the boss portion. A gear part 5 having a diameter smaller than that of the disc part 3 is integrally formed on the outer circumferential surface of a portion of the disc part 4 that projects downward from the disc part 2. Reference numeral 6 denotes an insertion hole formed in the axial center of the boss portion 4.

An annular recess 7 is formed on the upper surface of the disc portion 3 in a portion surrounding the boss portion 4, and a number of protrusions located concentrically with each other are formed between the recess 7 and the outer peripheral edge. Article 8, 8,... (Figure 1, 3
It is shown in the figure. ) is formed.

(b Friction wheel) [Figures 1 to 3] 9 is a friction wheel.

The friction wheel 9 has a base portion 1 having a slightly larger diameter than the disk portion 3 of the drive gear 2 and formed in a substantially disk shape.
0 and an annular outer wall portion 11 formed along the outer peripheral edge of the lower surface of the base portion 10, and an insertion hole 12 is formed in the center thereof. An annular protrusion is formed along the opening edge of the insertion hole 12 on the lower surface of the base 10 to have a substantially complementary relationship with the recess 7 formed in the disk portion 3 of the drive gear 2. 13 is formed, and a relatively shallow annular spring receiving groove 14 is formed in a portion of the upper surface of the base 10 around the insertion hole 12.

(c. Connection between the drive gear and the friction wheel) [Fig. 1] The drive gear 2 and the friction wheel 9 have protrusions 8, 8, . . . on the upper surface of the disc portion 3 of the drive gear 2. A friction plate 15 formed in a substantially circular band shape made of felt is positioned between the formed portion and a portion of the lower surface of the base 10 of the friction wheel 9 closer to the outer wall portion 11, and the insertion hole 12 of the friction wheel 9 is positioned. A substantially intermediate portion of the boss portion 4 of the drive gear 2 in the axial direction is inserted into the drive gear 2 so that the drive gear 2 and the drive gear 2 are connected to each other.

Note that the protrusion 13 of the friction wheel 9 is located in the recess 7 of the drive gear 2.
It is located inside without contacting it.

(d Driven gear) [Figures 1 to 3] 16 is a driven gear.

The driven gear 16 includes a gear portion 17 formed to have a somewhat smaller diameter than the base portion 10 of the friction wheel 9, and a substantially circular plate located on the upper surface of the gear portion 17 and having a slightly smaller diameter than the tooth root circle of the gear portion 17. Lower step part 1 formed in the shape of
8 and an upper step 19, which is located on the upper surface of the lower step 18 and is also formed in a substantially disk shape and has a somewhat smaller diameter than the lower step 18, are stacked coaxially with each other. It is formed in one piece.

A through hole 20 is provided at the axial center of the driven gear 16.
is formed, and the through hole 20 has a fitting part 20a located at the lower part of the through hole 20 and an insertion part 2 located at the upper part.
0b. That is, the fitting portion 20a connects the gear portion 17 and the lower stepped portion 18 of the shaft center portion of the driven gear 16.
The inner diameter of the inner diameter is such that the tip of the boss portion 4 formed on the drive gear 2 can be press-fitted therein. In addition, the insertion part 2
0b is continuous with the fitting part 20a, and its inner diameter is smaller than the inner diameter of the fitting part 20a.

Reference numeral 21 denotes an annular spring receiving groove formed relatively deeply around the through hole 20 on the lower surface of the driven gear 16 .

(e. Connection between driven gear, driving gear, and friction wheel)
[FIG. 1] The driven gear 16 is coupled to the drive gear 2 and the friction wheel 9 in the following manner. That is, the driven gear 16
A coil spring 22 having a relatively thick wire diameter is disposed between the spring receiving groove 21 formed in the friction wheel 9 and the spring receiving groove 14 formed in the friction wheel 9. Driven gear 1
It is press-fitted into the fitting portion 20a of the through hole 20 of No. 6.

The coil spring 22 is provided to be compressed by a predetermined amount between the friction wheel 9 and the driven gear 16, and the driven gear 16 has a drive gear 2 attached to the upper end surface of the fitting portion 20a of the through hole 20. The boss portion 4 is provided so that its lower surface is slightly spaced apart from the upper surface of the friction wheel 9 while the upper end surface of the boss portion 4 is in contact with the upper end surface of the boss portion 4 .

Thus, the drive gear 2 and the friction wheel 9 are pressed against each other via the friction plate 15 by the friction wheel 9 being pressed from above by the coil spring 22, and the friction wheel 9 and the driven gear 16 are pressed against each other via the friction plate 15. and are coupled to each other via the coil spring 22 so that rotational force is transmitted to each other.

(f Cap body) [Figures 1 to 3] 23 is a cap body.

The cap body 23 has a base portion 24 formed in a substantially circular band shape with a slightly larger diameter than the gear portion 17 of the driven gear 16.
, a boss portion 26 formed in a substantially annular protrusion shape so as to protrude downward from a portion of the lower surface of the base portion 24 along the large hole 25; and a boss portion 26 formed along the outer peripheral edge of the lower surface of the base portion 24. Relatively low annular protrusion 27
It consists of The inner diameter of the boss portion 26 is slightly smaller than the outer diameter of the upper stepped portion 19 of the driven gear 16. And the cap body 23 is the base 24 of this.
The upper step 19 of the driven gear 16 is press-fitted into the hole 25 with an idler and a coil spring, which will be described later, arranged between the lower surface of the driven gear 16 and the upper surface of the gear portion 17 of the driven gear 16. Driven gear 16
are integrally combined with.

(g idler) [Figures 1 to 3] 28 is an idler.

The idler 28 is formed into a plate shape with an approximately daruma-shaped outer shape, and has a large hole 2 at its base 28a, that is, a portion corresponding to the base of the daruma shape.
9 is formed, and annular protrusions 30 and 31 are formed along the upper opening edge and the lower opening edge of the hole 29. The diameter of the hole 29 is such that the upper step 19 of the driven gear 16 can be loosely fitted into it, and the outer diameter of the upper protrusion 30 is equal to the annular protrusion of the cap body 23. 27, and the lower protrusion 3
The outer diameter of the driven gear 16 is slightly smaller than the dedendum circle of the gear portion 17 of the driven gear 16.

The arm portion 28b of the idler 28, that is,
The part corresponding to the head of the Daruma shape is formed into a substantially trapezoidal planar shape, and the arm part 28b is bent into a crank shape when viewed from the side at a substantially intermediate position. Spring hook holes 33, 33' are formed at positions near both ends in the width direction of the arm portion 28b in the distal end portion of the portion between the portion 32 forming the intermediate portion and the hole 29.

Reference numeral 34 designates a connecting pin that projects downward from the tip of the arm portion 28b.

Thus, the lower part of the hole 29 of the idler 28 is loosely fitted onto the lower step part 18 of the driven gear 16, and the protrusion 31 on the lower side of the idler 28 is inserted into the upper surface of the gear part 17 of the driven gear 16. By being placed on the part where teeth are not formed, the driven gear 1
6 and the cap body 23 so as to be rotatable.

The upper end surface of the protrusion 30 on the upper side of the idler 28 is located at a certain distance from the lower surface of the base of the cap body 23.

In addition, the outer peripheral surface of the upper protrusion 30 is connected to the cap body 2.
They are located so as to be opposed to each other and separated from the inner peripheral surface of the annular protrusion 27 formed in 3. As a result, the base 28a of the idler 28
A portion of the upper surface along the upper protrusion 30 and a protrusion 27 on the lower surface of the base 24 of the cap body 23.
, and the upper protrusion 30 of the idler 28.
A substantially annular space is formed by the outer peripheral surface of the cap body 23 and the inner surface of the protrusion 27 of the cap body 23, and a coil spring, which will be described later, is arranged in this space.

(h coil spring) [Figures 1 to 3] 35 is a coil spring.

The coil spring 35 is made of a spring material having a relatively small wire diameter, and has an upper end and a lower end, that is, a ring 35a (hereinafter referred to as "upper contact end") located at the upper end of the coil spring 35. ) and the ring 35b located at the lower end of the coil spring 35 (hereinafter referred to as the "lower contact end ring").
The distal end portions 36b of are bent into a substantially U-shape facing substantially oppositely to each other. And the ring 3 at the upper contact end
A portion 36a' of the tip 36a of the coil 5a along the axial direction of the coil is longer than a portion 36b' of the tip 36b of the shaft 35b at the F-side contact end.

The diameter of the coil spring 35 is such that it can be loosely fitted onto the upper protrusion 30 of the idler 28.

The coil spring 35 formed in this way has its lower part fitted onto the upper protrusion 30 of the idler 28, and is placed between the idler 28 and the cap body 23 in a considerably compressed state, and Its upper end 36a is engaged with one spring hooking hole 33 formed in the arm 28b of the idler 28, and its lower end 36b is engaged with the other spring hooking hole 33'.
It is provided in the above-mentioned space by being attached to. Therefore, the coil spring 35 is rotated integrally with the idler 28.

Thus, the upper end 36a of the coil spring 35 does not come into contact with the lower surface of the base 24 of the cap body 23, but only the ring 35a at the upper contact end thereof, and the upper surface of the base 28a of the idler 28 The lower end 36b of the coil spring 35 is not contacted, and only the ring 35b at the lower contact end is contacted.

The idler 28 is then lightly pressed against the driven gear 16 by the coil spring 35.

The transmission gear block 1 constructed as described above has a support shaft 37 (see FIG. ) is inserted, and the driven gear 1 of the support shaft 37 is inserted.
A washer 38 for preventing slippage is engaged with the portion protruding upward from the through hole 20 of No. 6, so that the washer 38 is rotatably supported by the support shaft 37 while being prevented from slipping off from the support shaft 37. , the above-mentioned mutually fitted state and crimped state of the respective members constituting this are maintained.

Further, although not shown, a swing gear to be rotated is meshed with the gear portion 5 of the drive gear 2, and a gear to rotate the gear portion 17 of the transmission gear 16 is meshed with the gear portion 5 of the drive gear 2. Furthermore, a friction wheel that rotates the outer wall portion 11 of the friction wheel 9 is engaged with the outer wall portion 11 of the friction wheel 9 at a predetermined timing, that is, a gear (not shown) is engaged with the gear portion 17 of the driven gear 16. They are designed to be crimped when they are not engaged.

The connecting pin 34 of the idler 28 is connected to a swinging end of a swinging member (not shown).

(i Operation) Therefore, when the friction wheel 9 is rotationally driven, its rotational force is transmitted to the drive gear 2 via the friction plate 15 and to the driven gear 16 that rotates integrally with the drive gear 2. Ru. As a result, driven gear 1
6 is rotated integrally with the cap body 23 press-fitted therein, the rotational force is also transmitted to the idler 28 via the contact portion between the gear portion 17 of the driven gear 16 and the idler 28 and the coil spring 35. That will happen. Therefore, a rotational force is applied to the idler 28 in a predetermined direction.

By the way, the idler 28 is connected to its connecting pin 34.
Because the rotatable range is limited to an extremely small angular range by a swinging member (not shown) connected to the Unless it is in a state where it can move in accordance with the rotational force of these members, it will slip with respect to the driven gear 16 and the cap body 23. Therefore, the coil spring 35 slips against the cap body 23 except when the idler 28 is in the above-described state. However, only the ring 35a at the upper contact end of the coil spring 35 is in contact with the cap body 23, and the upper end 36a is not in contact. Therefore, even if a slip occurs between the coil spring 35 and the cap body 23, the edge portion of the end face of the coil spring 35 will never catch on the lower surface of the cap body 23.

Note that when the driven gear 16 is rotationally driven, its rotational force is transmitted to the drive gear 2.

(G Effect of the invention) As is clear from the above description, the mounting structure of the coil spring of the present invention is such that the spring contact surfaces that are contacted by the rings at the contact ends of the coil springs are positioned so as to face each other. and at least one of the coil springs is a mounting structure for a coil spring in a mechanism that requires a coil spring to be disposed between each contact surface of two members to be rotated or rotated in a state where the coil spring is compressed by a predetermined amount. It is characterized in that both ends are brought close to one end of the coil part, and the both ends are integrally supported by one of the two members.

Therefore, according to the present invention, the edge portion of the end surface of the coil spring does not come into contact with the spring contact surfaces of two members that are rotated or rotated relative to each other, so that the edge portion does not bite into the spring contact surface of the two members. It is possible to reliably prevent the occurrence of the so-called stuck phenomenon of the spring, which occurs when the spring is stuck.

Furthermore, since the present invention allows both ends of the coil spring to be supported by the member itself with which the coil spring is to come into contact, no extra member is required.

In the above-mentioned embodiment, the present invention was applied as a mounting structure for a coil spring in a transmission gear block of a tape recorder. One of them can be applied as a mounting structure for a coil spring in various mechanisms that require a coil spring to be disposed in a state compressed by a predetermined amount between contact surfaces of two members to be rotated or rotated.

[Brief explanation of drawings]

1 to 3 show an example of an embodiment in which the coil spring mounting structure of the present invention is applied as a coil spring mounting structure in a transmission gear block of a tape recorder, and FIG. 1 is a central vertical sectional side view of the transmission gear block. , Fig. 2 is an enlarged perspective view of the transmission gear block, Fig. 3 is an enlarged exploded perspective view showing the transmission gear block with a part cut away, and Figs. 4 and 5 show a conventional coil spring mounting structure in an idler device of a tape recorder. FIG. 4 is an exploded perspective view of a main part showing different examples of FIG. Explanation of symbols, 23... The other member of the two members, 28... One member of the two members, 35... Coil spring, 35a, 35b... Ring at the contact end of the coil spring, 36a , 36b... end of the coil spring.

Claims (1)

[Claims for Utility Model Registration] Each contact of two members, the spring contact surfaces of which are contacted by the rings at the contact ends of the coil springs, are positioned so as to face each other, and at least one of them is rotated or pivoted. A mounting structure for a coil spring in a mechanism that requires a coil spring to be placed in a state of being compressed by a predetermined amount between surfaces, wherein both ends of the coil spring are brought close to one end of a coil part, and the both ends are A mounting structure for a coil spring, characterized in that the coil spring is integrally supported by one of the two members.