JPH0725512B2 - Mechanical winch - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical winch, and more particularly, to a mechanical winch equipped with a detent mechanism that holds a shift lever for operating a clutch and a brake device in the operating position. Regarding

(Prior Art) A mechanical winch that winds or unwinds a rope with a drum to lift or tow a luggage or the like is widely used for loading and unloading work, for example, mounted on a land cruiser. The drum is optionally rotated by coupling with a transmission mechanism and a clutch, and the rotation is normally stopped by a brake device that stops a disc integrated with the drum. However, in the conventional braking device in which the outer surface of the disc integrated with the drum is used as the braking surface, there is a problem in that environmental resistance measures against rainwater and mud are troublesome.

Therefore, the present applicant intends to solve the above problems by
A mechanical winch (Japanese Patent Application No. 63-111166) is proposed in which the environment resistance is improved by housing the brake device (and clutch) in the gear case. Hereinafter, this is referred to as a prior invention.

FIG. 6 shows the invention of the prior application, the outline of which will be described below. A cylindrical portion 52 extending from one end of the drum 51 and a worm wheel 53 connected to a drive source are sealed in a gear case 56 with the same spline holes 54 and 55 formed on a common axis aligned with each other. . And the shift lever
The above-mentioned splines 54 and 55 are selectively engaged and disengaged via a spline hub 59 on a shift rod 58 that moves directly by a switching operation of 57. That is, the clutch is connected by the spline hub 59 engaging with both the spline holes 54 and 55, and the spline hole 55 of the worm wheel 53 is connected.
The clutch is designed to be disengaged by removing it from the.

On the other hand, the brake device includes a brake shoe 60 pivotally mounted at one end in an air space portion between an inner peripheral surface of the gear case 56 and an outer peripheral surface of the cylindrical portion 52, and an inner end portion of the shift rod 58. Side brake shaft 61 and the cylinder wall of the cylindrical portion 52, the brake shoe 60 by riding on the large diameter portion 62 of the brake shaft 61 when the shift rod 58 is operated to the braking position.
And a brake shoe actuating member (specifically consisting of balls 63 and springs 64) for pressing against the inner peripheral surface of the gear case 56.

The above clutch and brake device is operated by the axial movement of the shift rod 58 by the shift lever 57, and the operating position of the shift lever 57 is provided on the case cover 65 of the gear case 56 and is biased by the spring 66. It is held by a detent mechanism consisting of a detent ball 67 and three detent grooves 68 for clutch connection, clutch disengagement, and braking formed on the outer peripheral surface of the shift rod 58 at regular intervals in the axial direction. Has become.

The mechanical winch having such a structure has a feature that the clutch and brake device can be protected from rainwater and mud.

(Problems to be Solved by the Invention) Incidentally, in this type of mechanical winch, it is desirable that the mechanical winch is made as compact as possible because it is installed in a bumper of a specially equipped vehicle such as a land cruiser. . However, in the mechanical winch in which the above-mentioned clutch and brake device is housed in the gear case 56, in the detent mechanism in which the detent groove (or detent ball) is set in the shift rod 58, three grooves corresponding to each operation position are provided. It is necessary and requires a considerable space in view of the operation stroke, which is one of the factors that hinder the reduction of the overall length and weight of the winch.

Therefore, in view of the above problems, the present invention aims to reduce the size and weight of a mechanical winch by configuring a detent mechanism by using the components of a brake device that is an existing member of a mechanical winch. And

(Means for Solving the Problems) The present invention is configured as follows to solve the above problems.

That is, according to the present invention, the cylindrical portion extending from one end of the drum and the worm wheel connected to the drive source are sealed in the gear case by aligning the same spline hole formed on the common axis, and the shift lever is switched. It is configured to selectively engage and disengage both spline holes through a spline hub on a shift rod that moves directly by an operation, and further, a space portion between an inner peripheral surface of the gear case and an outer peripheral surface of the tubular portion. A brake shoe attached to the brake rod, a brake shaft provided on the inner end side of the shift rod, and a cylinder wall of the tubular portion, and the brake shaft when the shift rod is switched to the brake position. And a brake shoe operating member that rides on the large diameter portion of the brake shoe and presses the brake shoe against the inner peripheral surface of the gear case. In a canical winch, a brake that engages with the brake shoe operating member and holds the shift rod in the operating position when the shift rod is switched to the braking position at least on the outer circumference of the large diameter portion of the outer peripheral surface of the brake shaft. It is provided with a detent groove for position.

(Operation) In the mechanical winch configured as described above, the shift shaft is provided with the detent groove on the brake shaft, which is a component of the brake device, and the brake shoe operating member engages with the detent groove. Is added to the brake device, and therefore the shift rod length is shortened by at least the stroke between the brake position and the clutch disengagement position. As a result, the overall length of the winch body is shortened to make it compact, and the weight is reduced.

(Example) Hereinafter, the Example of this invention is concretely described based on drawing.

<Example 1> Example 1 shown in Figs. 1 to 3 will be described. First, a mechanical winch incorporating a clutch and a brake device will be described. In the figure, 1 is a substantially cylindrical gear case that houses a pair of worms 2 and worm wheels 3, and one circular hole 1a opened on the axis of the worm wheel 3 is closed by a case cover 4.
The tubular portion 5 extending from the inner wall of the case cover 4 has a boss 6 provided on one side of the worm wheel 3 as a plain bearing.
The circular hole portion 1b, which is fitted and supported through the 7a and has a diameter slightly smaller than that of the circular hole portion 1a which is extended in the vicinity of the center of the gear case 1, is different from the circular hole portion 1b provided on the other side of the worm wheel 3. A boss 8 having a diameter is fitted and supported through a plain bearing 7b.

The drum 10 on which the wire rope 9 is wound is rotatably supported by an end bracket on a cylindrical portion protruding outward from an outer flange (not shown), and is directed further inward from the inner flange 11 into the gear case 1. A cylindrical portion (12) is inserted so as to protrude. The outer diameter of the cylindrical portion 12 is formed so as to gradually decrease toward the tip, and the maximum diameter portion of the base portion closes the rim of the other circular hole portion 1c of the gear case 1 via the dust seal 13. The next middle diameter part is the circular hole part 1c
With the relative annular space 14 between them, the plain bearing 7b is fitted, and the bearing is supported in a form coexisting with the worm wheel 3. Further, a small-diameter portion that continues extends to almost the central portion of the worm wheel 3. ing.

The same spline holes 15 and 16 which are aligned with each other are provided in the contact area of the worm wheel 3 and the cylindrical portion 12 fitted therein.
And a spline hub 17 that selectively engages and disengages the spline holes 15 and 16 is engaged to form a so-called clutch mechanism.
17 is operated by a shift rod 18 that extends through the center of the case cover 4 slidably in the axial direction and extends into the gear case 1.

A substantially cylindrical brake shaft 19 is fitted to the inner end that is the extending end of the shift rod 18, and the brake shaft 19 has a large diameter portion 19a that fits into the inner hole 12a of the cylindrical portion 12.
And a guide portion 19b having a smaller diameter than this, and an inclined cam surface 19c connecting these portions. The spline hub 17 loosely fitted to the shift rod 18 has a retaining ring 20 at its outer end.
And a retaining ring by a compression spring 21 interposed between the inner end and the brake shaft 19.
It is biased toward the 20 side. Further, the shift rod 18 is linked to a shift lever 23, which is attached to the outside of the case cover 4 via a pin 22 so as to be tiltable, via a pin 24, and is moved forward and backward based on a tilting operation of the shift lever 23. It

On the other hand, as shown in FIG. 3, two bosses 25 symmetrically projecting to the annular space 14 are formed in the medium diameter portion of the cylindrical portion 12 of the drum 10, and the boss 25 Brake shoe curvedly extending in the rewinding direction of the drum 10
The base end of 26 is pivotally attached via a pin 27, and the brake shoe 26 is a torsion spring connected around the pin 27.
The tip 28 is urged by 28 against the centrifugal force of rotation of the drum 10 so as not to float. A brake lining 29 is attached to the outer surface of the tip of the brake shoe 26.

Also, the cylindrical portion 12 corresponding to the tip of the brake shoe 26
A through hole 30 that communicates the annular space 14 and the inner hole 12a is formed in the cylindrical wall of the through hole 30, and a ball 31 for brake operation is always held in the guide portion 19b of the brake shaft 19 in the through hole 30. It is inserted in the form that is, and this ball 31
When the brake shaft 19 is operated together with the shift rod 18 to the brake position, the brake shaft 26 enters the through hole 30 by riding on the large diameter portion 19a via the cam surface 19c, and the brake shoe 26 is connected to the circle through the spring 32. It is configured to press toward the peripheral surface of the hole 1c. That is, the ball 31 and the spring 32 form a brake shoe operating member.

Next, a detent mechanism that holds the shift lever 23 for operating the clutch and brake device in the operating position will be described.

First, a detent mechanism for the clutch connecting position and the clutch disengaging position is formed at the fitting portion between the shift rod 18 and the case cover 4. This detent mechanism includes a detent ball 34 fitted in a through hole 33 formed in the cylindrical thick portion of the case cover 4 in the radial direction, and a detent ball 34 for this.
A detent spring 35 that urges toward the 18 side, and two detent grooves 36 and 37 for the clutch connection position and the clutch disengagement position that are formed on the outer peripheral surface of the shift rod 18 at regular intervals in the axial direction. The detent groove 36,
Both 37 are formed in a V-shaped cross section.

On the other hand, on the outer peripheral surface of the large diameter portion 19a of the brake shaft 19, a detent groove 38 having a V-shaped cross section for brake position is formed, and after the ball 31 for brake operation rides on the large diameter portion 19a. Since the ball 31 is engaged with the detent groove 38 in this case, it is considered that the braking force is reduced. Therefore, the spring 32 is reinforced to compensate for this. That is, the detent mechanism for the brake position is configured by using the constituent members of the brake device.

The mechanical winch configured as described above is mounted on a bumper of a specially equipped vehicle such as a land cruiser, and the worm 2 is connected to a power take-off shaft of the vehicle.

This embodiment is constructed as described above, and when the shift lever 23 is in the clutch disengaged position shown by the solid line in FIG. 1, the spline hub 17 is pulled out from the spline hole 15 of the worm wheel 3. The clutch disengaged position is held by the detent ball 34 engaging with the detent groove 36 on the left side in the drawing. And in this state the drum 10
Is allowed to rotate freely by external force,
The wire rope 9 can be withdrawn at will.

When the shift lever 23 is operated from the clutch disengaged position to the clutch connected position on the left side shown by the alternate long and short dash line in FIG. 1 and the shift rod 18 is pulled out, the spline hub 17 is out of phase with the spline hole 15 of the worm wheel 3. If they match, they move together with the shift rod 18, and if they do not match, the compression spring 21 interposed between them and the brake shaft 19
Contracts once and then stops, and when they match, the spline hole
Mesh with 15. Therefore, the rotation of the worm wheel 3 is transmitted to the drum 10 and the wire rope 9 is wound up. The clutch connection position is held by the detent ball 34 engaging with the detent groove 37 on the right side in the drawing.

Further, when the shift lever 23 is operated from the clutch disengaged position to the brake position on the right side indicated by the chain double-dashed line in FIG. 1 and the shift rod 18 is pushed in, the cam surface 19b of the brake shaft 19 that moves together with the shift rod 18 Since the ball 31 for brake operation is pushed up by the brake operation and enters the through hole 30, the tip portion of the brake shoe 26 is urged outward via the spring 32 in the through hole 30, and the brake lining 29 is A braking force is applied to the drum 10 by being pressed against the peripheral surface of the circular hole portion 1c. As described above, the ball 31 pushed up by the cam surface 19b finally rides on the large diameter portion 19a, and then the detent groove 3 for the brake position of the large diameter portion 19a.
8 and thus the shift lever 23 is held in the brake operating position.

Now, in the present embodiment, the detent mechanism for holding the shift lever 23 at the brake device position is configured by using the constituent members of the brake device, so that the shift rod
Since it is only necessary to form two detent grooves 36 and 37 for the clutch on the 18, it is possible to shorten the shift rod 18 by the stroke from the clutch disengaged position to the brake position, and accordingly the winch body. The overall length of is compact and lightweight. Further, since the brake shaft 18 has the detent groove 38, it is possible to surely apply the brake when the brake is actuated, and the click feeling of the shift lever 23 can be the same as that when the shift rod 18 is provided. Is.

Example 2 Next, Example 2 of the present invention shown in FIG. 4 will be described. In the second embodiment, the detent groove 38 for the brake position, which is formed in the large diameter portion 19a of the brake shaft 19, is constituted by a taper surface having a downward slope toward the shaft end side. Configured similarly. Therefore, when the brake lever is operated by the shift lever 23, the ball 31 is pushed up by the cam surface 19c of the brake shaft 19, and when the ball 31 exceeds the cam surface 19c, the ball 31 is stopped by the slope of the detent groove 38 formed of the tapered surface. In this case, the brake shaft 18 receives a reaction force of the braking force in the direction of being pushed into the gear case 1. For this reaction force, for example, the shift lever 23 comes into contact with a part of the case cover 4. It can be accepted by configuring.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. In the third embodiment, not only the detent groove 38 for the brake position but also the detent grooves 36, 37 for the clutch connecting position and the clutch disengaging position are formed in the brake shut 19. That is, the detent groove 38 for the brake position is formed on the outer peripheral surface of the large diameter portion 19a as in the first embodiment, and the two detent grooves 36 and 37 for the clutch connecting position and the clutch disengaging position are small-diameter guide portions. It is formed on the outer peripheral surface of 19b, and in this case, the axial length of the brake shaft 19 is set to be slightly longer if necessary.

Therefore, in the third embodiment, the detent mechanism on the shift rod 18 side is completely abolished, so the shift rod 18
The length is greatly shortened, which greatly contributes to making the winch body compact and lightweight. Moreover, since all the constituent members of the detent mechanism use the constituent members of the brake device, the number of parts is reduced, the cost is reduced, and the case cover 4 can be made thin. Weight is reduced.

The ball 31 as the brake actuating member described in the illustrated embodiment can be changed to, for example, a rod.

(Effects of the Invention) As described in detail above, the mechanical winch of the present invention is
By configuring the detent mechanism using the components of the brake device, the shift rod length can be shortened, and the winch body can be made compact and lightweight. Therefore, it is limited to the bumper of a vehicle. It is extremely effective when installed in a large space.

[Brief description of drawings]

1 is a longitudinal sectional view showing a mechanical winch of Embodiment 1 of the present invention, FIG. 2 is an enlarged sectional view in the vicinity of a brake device, FIG. 3 is a sectional view taken along line III-III of FIG. 1, and FIG. Second Embodiment A second embodiment of the present invention, FIG. 5 is a sectional view showing a third embodiment of the present invention, and FIG. 6 is a longitudinal sectional view showing a conventional mechanical winch. 1 ... Gear case, 3 ... Worm wheel 10 ... Drum, 12 ... Cylindrical part 15,16 ... Spline hole 17 ... Spline hub, 18 ... Shift rod 19 ... Brake shaft, 19a ... Large diameter part 23 …… Shift lever, 26 …… Brake shoe 31 …… Ball, 38 …… Detent groove

Claims (1)

[Claims] Claim: What is claimed is: 1. A cylinder portion extending from one end of a drum and a worm wheel connected to a drive source are sealed in a gear case by aligning the same spline holes formed on a common axis, and the shift lever is switched. It is configured to selectively engage and disengage the both spline holes via a spline hub on a shift rod that moves directly by an operation, and further, an air space portion between an inner peripheral surface of the gear case and an outer peripheral surface of the tubular portion. A brake shoe attached to the brake rod, a brake shaft provided on the inner end side of the shift rod, and a cylinder wall of the tubular portion, and the brake shaft when the shift rod is switched to the brake position. And a brake device including a brake shoe operating member that presses the brake shoe against the inner peripheral surface of the gear case by riding on the large diameter part of the In inches, for a brake position that engages the brake shoe operating member to hold the shift rod in the operating position when the shift rod is switched to the braking position at least on the outer circumference of the large diameter portion of the outer peripheral surface of the brake shaft. Mechanical winch with a detent groove.