JPH0729757B2 - Small tow hoist - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small tow hoist.

[0002]

2. Description of the Related Art Hitherto, as a traction hoisting machine of this type, there has been a free-running device in a lever type small hoisting and traction device described in Japanese Patent Publication No. Sho 63-3838.

[0003]

In the above-mentioned traction device,
In the operation of switching from the idling (idling) state of the brake to the braking state and hoisting the chain, the load is applied to the chain while the idling handle is consciously operated to bring the braking mechanism into the braking state. Next, the switching lever had to be wound up (normal rotation position) to wind up the chain, which made smooth and quick work impossible.

Further, when a sudden load is applied to the chain in the idling state, the chain is temporarily braked. However, when the load is removed, the chain returns to the idling state again, and there is a problem that the chain falls when the load is light. .

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to a disk hub fixed to a pinion shaft.
And the screw part of the pinion shaft so that it can be screwed back and forth.
Disc nut, and the disc hub and disc nut
Ratchet wheel and brake liner interposed between
And a idling switching member that constitutes a brake mechanism including
Is attached to the above pinion shaft so as to rotate integrally.
The spring receiving portion of the idling switching member to the disc nut
Between the disc nut and the spring receiving part.
Then, by twisting the disc nut,
Pressed against the ratchet wheel and brake lining
A torsion spring to
The engaging knock formed in the hole of the disc nut.
A locking ball that can be freely engaged and disengaged with
Springs that maintain the locked state with the notches.
In addition, the disc
The ratchet wheel and the brake
The ball is placed in the notch when it is separated from the inning.
Arrange the notch and the ball so that the notch
And the ball is locked, the torsion spring of the above torsion spring
From the force that tries to separate the ball from the notch due to the force
Also has a large locking force between the notch and the ball.
It

[0006]

In a normal state, the rotational torque of the torsion spring exerts a force in the operating direction of the brake mechanism on the disc nut to forcibly tighten the brake. Therefore, even if a light load is applied to the load chain, the braking state can be reliably maintained.

Further, from the idling state in which the brake is loosened,
If a load is applied to the load chain in the winding state (normal rotation) and the operating lever is swung, the braking state is automatically restored and the winding operation can be performed immediately.

Also, when the notch and the ball are locked.
The notch and ball are released by the torsional elasticity of the torsion spring.
The locking force between the notch and the ball is greater than the force to
Since it has been set, it will return from the idling state to the braking state arbitrarily
Can be prevented.

Then, in the idling state, the load chain 11
A sudden load that exceeds the locking force between the notch and the ball.
If the ball comes out of the notch, keep it in the torsion spring.
The disc nut is instantly screwed by the twisting elastic force
Proceed to automatically restore the braking state.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiments.

In FIG. 1, 1 is a pinion shaft to which a pinion 2 is fixed at one end, 3 is a load sheave which is rotatably fitted onto the shaft 1, and the load sheave 3 has load metals 4 and 4 interposed therebetween. And is pivotally attached to the side plates 5 and 5.

Reference numeral 6 is a load gear fixed to the load sheave 3, and is always connected to the pinion 2 via a reduction gear group 7.

Reference numeral 8 denotes a gear box, which is a reduction gear group 7
Etc. are surrounded and fixed to one side plate 5. 9
Is a ratchet cover, which is fixed to the other side plate 5.

An upper hook 10 is attached to the side plates 5 and 5 so as to be rotatable and swingable.

Reference numeral 11 denotes a load chain suspended from the load sheave 3 and suspended, and a load hook is attached to a lower end outside the drawing to apply a load.

A disk hub 12 is fixed to the shaft 1 and comprises a small cylindrical portion 12a and an outer flange portion 12b.

Reference numeral 13 is a disc nut, and the shaft 1
To the screw part 14 (which is the right-hand screw) of the disc nut 13
The screw holes 15 are screwed in such a manner that they can move forward and backward, and are screwed together.

The disc hub 12 and the disc nut 1
Ratchet wheel 16 and brake lining 1 between 3
7 and 17 are interposed so that they can be pressed freely.

In the illustrated example, the small cylindrical portion 1 of the disk hub 12 is shown.
A ratchet wheel in which the interlocking ring 18 is rotatably fitted to the outer peripheral surface 2a, serrations, splines, etc. are formed on the outer peripheral surface of the interlocking ring 18, and corresponding serrations, splines, etc. are formed on the inner surface of the through hole. 16 and the brake linings 17, 17 are fitted to each other to prevent relative rotation between the contact surfaces of the ratchet wheel 16 and the brake linings 17.

Further, the braking pawls 19 and 19 are provided on the side plate 5 and engage with the concave and convex teeth on the outer periphery of the ratchet wheel 16.

A brake mechanism 20 is constituted by the disk hub 12, the disk nut 13, the interlocking ring 18, the ratchet wheel 16, the brake linings 17, 17 and the braking pawls 19 described above.

Reference numeral 21 denotes a lever for manual operation, which is mounted around the axis L of the shaft 1 so as to be swingable.

The lever 21 has a switching piece 23 having a forward / reverse rotation claw piece which engages / disengages with the switching gear portion 22 of the disc nut 13, and is built in the base end portion thereof.
3 can be switched to forward / reverse / neutral by operating the handle 24.

Further, as shown in FIG. 2, the idling switching member 28 integrally including the handle operating portion 25 and the spring receiving portion 27 integrally rotates (with the shaft 1) to the other end of the shaft 1 via the serration 26 or the like. Mounted in a shape.

At the same time, the spring receiving portion 27 is rotatably internally contained in a circular hole portion 29 formed continuously with the screw hole 15 of the disc nut 13.

Further, as shown in FIGS. 2 and 3, a pair of circular holes 35, 35 are formed in the large diameter portion 34 of the spring receiving portion 27 which faces the hole portion 29 of the disc nut 13 with a slight gap.
Are formed in the radial direction.

Then, each of the circular holes 35 is provided with a locking bow.
And a notch 3 which will be described later by elastically urging the ball 37.
And a spring 36 that keeps the locked state with 8 .

Specifically, the spring 36 is provided in the circular hole 35.
And after inserting the locking ball 37, the peripheral portion 35 of the circular hole 35
By plastically deforming a by caulking or the like as shown in the figure, only the peripheral edge portion 35a is larger than the inner diameter of the circular hole 35 so that the locking ball 37 can be projected outward from the peripheral edge portion 35a by a predetermined amount. Is also made slightly smaller.

The peripheral edge portion 35a prevents the locking ball 37 and the spring 36 from scattering when the spring receiving portion 27 is pulled out from the hole portion 29 of the disc nut 13.

The locking balls 37, 37 are formed in a pair of semi-circular engagement notches 38, 38 formed in the axial direction of the disk nut 13 so as to face the hole 29 (see FIGS. 3 and 5). (Like) It can be freely engaged and disengaged.

Reference numeral 30 is a torsion spring which is externally fitted to the small diameter portion 33 of the spring receiving portion 27, and one end of this spring 30 is inserted and attached to a small hole 31 (in the axial direction) of the disc nut 13. , The other end is a small groove 32 (in the axial direction) of the spring receiving portion 27.
Is attached to.

In this way, the disc nut 13 and the bar nut are
The disc snapping is caused between the receiving parts 27 by the torsional elastic force.
The ratchet 13 by screwing the lever 13 (in the direction of arrow T shown in FIG. 2).
Push on the wheel 16 and the brake linings 17, 17.
A torsion spring 30 for pressing is interposed.

A disc nut against the torsional elastic force
13 is screwed back (in the direction of arrow E shown in FIG. 4) to ratchet
Separated from toe wheel 16 and brake linings 17, 17.
The ball 37 will be locked in the notch 38 in the state in which
The notch 38 and the ball 37 are arranged as shown in FIG.

Further, the notch 38 and the ball 37 are in a locked state.
The notch 3 due to the torsional elastic force of the torsion spring 30 in the state
8 and notch 3 rather than the force to separate ball 37
The locking force between the ball 8 and the ball 37 is set to be large.

Reference numeral 39 denotes a feed handle, in which the concave grooves 40 of the disc nut 13 are fitted into the convex teeth 41 of the feed handle 39.
It can be attached by engaging .... This feed handle 39
Thus, the disc nut 13 can be rotated.

Further, the feed handle 39 and the idling switching member 2
A push spring 55 is interposed between the handle 8 and the handle operating portion 25 to prevent the feed handle 39 from rattling. The push spring 55 is interposed so that the feed handle 39 and the idling switching member 28 can rotate independently of each other.

1, 2 and 3 show the braking state of the brake mechanism 20. In this state, the disc nut 13 is screwed by the torsional elastic force of the spring 30.
The disc nut 13 is elastically urged by the force of rotating about four times, and the disc nut 13 moves in the direction of pressing the brake lining 17 (direction of arrow T).

Therefore, in the state shown in FIGS. 1 to 3, the brake linings 17, 17 and the ratchet wheel 16 are
The disc nut 13 presses and maintains the braking state.

In the braking state of the brake mechanism 20,
The balls 37, 37 of the spring receiving portion 27 are orthogonal to the notches 38, 38 of the disc nut 13.

4 and 5 show the idling state in which the brake mechanism 20 is not braked. To get into this state,
From the state of FIGS. 1 to 3, the switching piece 23 is reversely rotated (lowered).
In this state, the handle operating portion 25 of the idling switching member 28 is grasped by hand and rotated by about 90 ° to the right as indicated by arrow R.

Then, the shaft 1, the springs 36, 36 and the ball 3 are integrated with the rotation of the idling switching member 28.
7, 37 rotate about 90 ° in the direction of arrow R.

Then, as shown in FIGS. 4 and 5, the spring 3
The balls 37, 37 are elastically urged by 6, 6 to abut or closely contact the notches 38, 38, and the disc nut 13 is rotated by the shaft 1 so that the arrow E
The brake lining 17 to move to the non-braking idling state.

In this idling state, if the switching piece 23 (see FIG. 1) is set to the neutral state, the load sheave 3 (see FIG. 1).
Can rotate freely, so that the load chain 11 (see FIG. 1) can freely travel.

At this time, in the load chain 11,
(Ball 37, spring 36, notch 38 and spring 3
When a sudden load is applied (exceeding the locking force between the idling switching member 28 and the disc nut 13 determined by 0, etc.), the balls 37, 37 come off the notches 38, 38, and the torsion spring 3
With the torsional elastic force stored at 0, the disc nut 13 instantaneously moves in the direction opposite to the E direction, and the idling state is automatically restored to the braking state shown in FIGS.

Even when the load applied to the load chain 11 is removed, the spring 30 causes the disc nut 13 to be forcibly pressed against the brake lining 17 as described above, so that the brake state does not return to the idling state. Can be maintained reliably and, in this state, the feed handle 39
By rotating the by hand, the unloaded load chain 11 can be wound up and down.

Further, in the idling state (FIGS. 4 and 5), unless the load is suddenly applied to the load chain 11 as described above, the balls 37, 37 are locked in the notches 38, 38. Shaft 1 keeps disk nut 1 in place
It rotates together with 3 and never returns to the braking state without permission.

However, in order to reverse the idling state to the braking state, the switching piece 23 is normally rotated (raised), a proper load is applied to the load chain 11, and the lever 21 is swung. Often, the balls 37, 37 in the locked state are disengaged from the notches 38, 38, and the braking state shown in FIGS. 1 to 3 is immediately established.

Next, FIGS. 6, 7 and 8 show another embodiment in which an overload preventing mechanism 42 is additionally provided.
3 shows the case where a one-way clutch hub is used.

The overload prevention mechanism 42 includes a clutch hub (disc nut) 13, a slip gear 47, and a roller 49.
..., fixed disk 51, disc spring 52, and nut member 53
Etc.

The clutch hub (disc nut) 13 is
The outer peripheral part 43 in contact with the brake lining 17, the outer peripheral groove 44 in sliding contact with the roller 49, the serration 45, and the male screw part 46 are provided on the outer peripheral surface.

Clutch linings 48, 48 are baked and stretched on both end surfaces of the slip gear 47, and a plurality of cam grooves 50 for holding a roller 49 movably in the circumferential direction are formed on the inner peripheral surface of the slip gear 47. (Three locations in the illustrated example) are formed.

Then, the clutch hub (disc nut)
13, the clutch lining 48 of one of the slip gears 47 is brought into contact with the outer flange portion 43 of the roller 13, and the roller 49 is connected to the cam groove 5
It is held between 0 and the outer peripheral groove 44, and the slip gear 47 is externally fitted to the clutch hub (disc nut) 13.

At this time, in the gap 54 between the cam groove 50 and the outer peripheral groove 44, one is narrower than the outer diameter dimension of the roller 49 and the other is wide.

The forward rotation claw piece and the reverse rotation claw piece of the switching piece 23 at the base of the lever 21 are selectively locked to the switching gear portion 22 on the outer peripheral side of the slip gear 47.

Further, a fixed disc 51 contacts the other clutch lining 48 of the slip gear 47, and this fixed disc 51 is movable in the axial direction via the serration 45 of the clutch hub (disc nut) 13. Mounted.

Then, the nut member 53 elastically presses the fixed disc 51 against the slip gear 47 via the disc spring 52, so that the slip gear 47 and the clutch hub (disc nut) 13 and the clutch lining 48, etc. It is possible to rotate integrally by frictional force.

Load chain 11 operated by lever 21
If the load chain 11 is overloaded during winding, the slip gear 47 slips on the clutch hub (disc nut) 13.

By rotating and adjusting the screwing position of the nut member 53 to the male screw part 46, the strength of the elastic pressing force of the disc spring 52, that is, the slip gear 47, causes the clutch hub (disc nut) 13 to move. The limit value of the pressing frictional force that slips (that is, the operation set value of the overload prevention mechanism 42) can be adjusted.

The feed handle 39 is provided so as to surround the nut member 53 from the outside, and the feed handle 39 and the nut member 53 are meshed or locked with each other so that they can rotate integrally. Specifically, the feed handle 39 is
The concave grooves 40 ... And the convex teeth 41 ... are engaged with each other and attached to the nut member 53 (as in FIG. 3).

The feed handle 39 and the nut member 53
The structure for engaging or locking the can be variously changed in design. In this way, the clutch hub (disc nut)
13, the feed handle 39, through the nut member 53,
Mount so that it can rotate integrally.

When the load chain 11 is wound up, however, in the one-way clutch composed of the roller 49, the cam groove 50, etc., the roller 49 (as shown in FIG. 8) moves to the wide side of the gap 54. In the loose insertion state, the lever 21
Is applied to the slip gear 47.
Through the clutch linings 48, 48 of the outer collar 43
And transmitted from the fixed disc 51 to the clutch hub (disc nut) 13.

During winding, the roller 49 moves to the narrow side of the gap 54, forming a wedge between the cam groove 50 and the outer peripheral groove 44, and the clutch hub (disc nut) 13 The slip gear 47 is coupled, and the rotational force given by the operation of the lever 21 is transmitted to the clutch hub (disc nut) 13 via the roller 49.

Also in the tow hoisting machine with the overload preventing mechanism 42 of the illustrated example, as in the previous embodiment (of FIG. 1), if it is rotated by about 90 ° in the direction of arrow R, FIG. And as shown in Figure 10,
The clutch hub (disc nut) 13 moves in the direction of arrow E and becomes idling.

On the contrary, in order to bring the braking states of FIGS. 6 to 8 into consideration, it is sufficient to apply an appropriate load to the load chain 11 to bring the switching piece 23 into the normal rotation (winding) state and swing the lever 21. The braking state is immediately changed from the idling state.

Further, according to the embodiment shown in FIGS. 6 to 8, the feed handle 3 is provided in a state where all parts of the small tow hoist are assembled.
A strong rotation torque is applied to 9 to slightly rotate the nut member 53, which is fixed by a snap ring or the like, to set the operation of the overload prevention mechanism 42 without disassembling the idling switching member 28, the feed handle 39, and the like. You can easily fine-tune the value.

As described above, in order to apply a strong rotational torque to the feed handle 39, for example, an adjusting jig 56 as shown in FIG. 11 may be fitted on the feed handle 39 and rotated by hand or the like. The adjusting jig 56 includes a cylindrical portion 58 in which a convex portion 57 that engages with the holding concave portion 39a of the feed handle 39 is provided, and a belt plate lever portion 59 for holding and rotating operation.
Consists of.

According to the present invention, the overload prevention mechanism 4
Other than the parts such as the clutch hub (disc nut) 13 that form part 2, the parts of the embodiment of FIG. 5 and the embodiment of FIG. 1 can be shared.

[0068]

The present invention has the following great effects.

Once in the braking state, the torque due to the rotational torque of the torsion spring 30 that advances in the operating direction of the brake mechanism 20 always acts on the disc nut 13 and does not return to the idling state without permission. The braking state can be reliably maintained even under load. That is, it is possible to prevent an accident in which the load chain 11 falls due to a light load.

It is possible to easily and quickly switch between the braking state and the idling state, and particularly when the idling state is switched to the braking state to wind up the chain, the handle operating portion 25 of the idling switching member 28 is more conscious than in the conventional case. Since it is possible to save the trouble of manually operating and restoring the braking state, the hoisting work can be performed easily and quickly, and the work efficiency can be further improved.

Release the brake to release the ball 3 in the notch 38.
In the idling state in which 7 is locked, the notch 38 and the ball 37
The locking force of the notch 38 and the ball 37 due to the torsional elastic force.
Is stronger than the force that tries to leave the
It is possible to effectively prevent returning to the braking state where the key is tightened, and it is easy to use
I have good hands.

Idling with ball 37 locked in notch 38
In this state, the ball 37 and the notch 38 are
The strong torque that exceeds the locking force of is applied to the pinion shaft 1.
Then, the ball 37 and the notch 38 come off, and the torsion bar
The stored torsional elasticity of Ne 30 is released,
The disc nut 13 is screwed by the torsional elastic force and
It is possible to automatically switch to the braking state where the rake is tightened.
it can.

[Brief description of drawings]

FIG. 1 is a sectional front view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts in a braking state.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a cross-sectional view of a main part in an idling state.

5 is a sectional view taken along line BB of FIG.

FIG. 6 is a sectional front view showing another embodiment.

FIG. 7 is a cross-sectional view of essential parts in a braking state.

8 is a sectional view taken along line CC of FIG.

FIG. 9 is a cross-sectional view of a main part in a state of idling.

10 is a cross-sectional view taken along the line DD of FIG. 9.

FIG. 11 is an overall view showing a usage state of an adjustment jig.

[Explanation of symbols]

 1 Pinion shaft 13 Disc nut 20 Brake mechanism 25 Handle operating part 27 Spring receiving part 28 Idling switching member 29 Hole 30 Torsion spring 36 Spring 37 Ball 38 Notch 39 Feed handle

Claims (1)

[Claims] 1. A disc fixed to a pinion shaft 1.
The hub 12 and the threaded portion 14 of the pinion shaft 1 are threaded.
The disc nut 13 that is screwed in a retractable manner and the disc nut
The ratchet installed between the sleeve 12 and the disc nut 13.
To wheel 16 and brake linings 17, 17,
The brake mechanism 20 provided with the idle rotation switching member 28 is configured.
When it is attached to the pinion shaft 1 so as to rotate integrally,
The spring receiving portion 27 of the idling switching member 28 is
The disk nut is internally provided in the hole 29 of the nut 13.
Between the spring 13 and the spring receiving portion 27 due to the torsional elastic force.
The ratchet wheel 1 by screwing the screw nut 13
6 and screws for pressing the brake linings 17,
The spring 30 is interposed, and the spring receiving portion 27 is further provided.
Is formed on the hole 29 of the disc nut 13.
The engaging ball 37 that can be engaged with and disengaged from the combination notch 38, and the ball
Retains the notch 38 by keeping the engagement with the notch 38.
And a spring 36 for
The disk nut 13 is screwed back against the resilience
Ratchet wheel 16 and brake lining 17,
The ball 3 is inserted into the notch 38 while being separated from the ball 17.
The notch 38 and the ball 37 are arranged so that 7 is locked.
Then, when the notch 38 and the ball 37 are locked,
The notch 38 and the bow due to the torsional elastic force of the torsion spring 30.
The notch 38 and
A small towing hoist characterized by a large locking force of the roll 37 .