JP5116626B2 - Input/output device using a mainspring - Google Patents

Description

This invention relates to a spring-based input/output device that stores mechanical energy in a constant-load spring and releases that energy for use.

Constant force springs usually have the characteristic that they will not return once wound all the way from the unwinding drum, so they are usually specially constructed so that they cannot be wound all the way. Also, if the spring is wound too much, problems such as the spring breaking or not returning (poor return) occur. Therefore, in the past, when a constant force spring was used to open and close a shutter or sliding door, it was necessary to take measures such as leaving some leeway in the spring length so that the spring would not be overwound when it was moved all the way to the end, or to use special control such as stopping the input or disconnecting the spring just before the overwinding occurs.

However, when the stroke of movement is limited, such as in shutters or sliding doors, allowing some leeway in the spring length is sufficient and constant-load springs function normally; however, for example, in the "audio guide device" (see Patent No. 4143765) developed by the present applicant, where a spring is wound by an unspecified number of people to store energy for generating sound, or when there is continuous input from hydraulic or wind power, the spring can become overwound and cause problems. Furthermore, when using overwind prevention control, high costs are unavoidable, and daily adjustments are required to correct errors, making it difficult to achieve reliability and not necessarily a solution to the problem.

In consideration of the above situation, this invention uses a main spring and a secondary spring, each of which is a constant-load spring that acts on the input and output, and the relationship between these springs can eliminate problems caused by overwinding, so the objective of the invention is to provide an input/output device using a spring that has a reasonably simple structure within the input/output configuration and can operate reliably without the need for adjustment.

In order to solve the above problems, the first invention provides an input/output device using a spring, which is characterized in that a composite drum is fixedly attached to an input/output shaft that rotates forward and outputs reversely, and in which a main spring and a secondary spring are wound against their elasticity, and a main unwinding drum and a secondary unwinding drum, in which the main spring and the secondary spring are always in standby winding, are rotatably supported on a parallel pair of shafts to the input/output shaft. The main and secondary springs are wound in standby winding against elasticity by the forward rotation of the composite drum accompanying the input, and then the main and secondary springs are wound in the main and secondary unwinding drums, and the force of returning them to their original state is used to provide a torque for reverse rotation on the input/output shaft. In the secondary unwinding drum, the secondary spring is wound up first, completing the return, and at the same time, there is an unwound portion on the main unwinding drum, and a difference in the length of the unwound portion between the main spring and the secondary spring is set.

In the second invention, an output shaft is provided in parallel with an input shaft via a one-way connecting clutch that transmits only the force that rotates the output shaft in the forward direction and a direction-changing mechanism that changes the direction of force transmission, and a parallel pair of shafts are provided in parallel with the input shaft. A composite drum is fixedly attached to the output shaft, and has a main winding groove and a sub winding groove that winds the main spring and the sub spring against their respective elastic forces. The parallel pair of shafts rotatably support a main unwinding drum and a sub unwinding drum, on which the main spring and the sub spring are always wound in standby. The spring is wound up against elasticity in the main winding groove and the sub winding groove by the forward rotation of the composite drum due to the input, and then the force of returning the spring to the main unwinding drum and the sub unwinding drum produces a reverse rotation torque as an output on the output shaft. In the sub unwinding drum, the sub spring is unwound first and completes the return, and at the same time, there is an unwound portion on the main unwinding drum at that point. This is a spring input/output device characterized by having a difference in the length of the remaining winding between the main spring and the sub spring.

Because the input/output device using the spring is configured as described above, if the input continues even when the spring is close to being overwound, the short spring will first be wound to the end, and this overwinding will cause a locked state on the secondary winding drum, causing a return failure. However, the long spring has not yet reached an overwound state, and since there is still some unwound material on the main winding drum, this becomes the driving force for rewinding the main spring onto the main winding drum, causing the composite drum to rotate in the reverse direction (output rotation), which in turn unwinds the secondary spring from the composite drum, creating room for the secondary spring to rewind onto the secondary winding drum. In other words, the remaining winding on the main winding drum acts as a helping hand to release the locked state of the secondary winding drum, and as a result, the entire spring set functions normally.

As explained above, the input/output device of this invention uses a main spring and a secondary spring, both of which are constant-load springs that act on the input and output, and can eliminate problems associated with overwinding simply by adjusting the length of the springs. This eliminates the problem in a rational way, making the device simple as a whole. Furthermore, it has the excellent effect of preventing problems without the need for special adjustments, and making it possible to provide an inexpensive input/output device using springs.

In addition, according to claim 3, the torque limiter can be used to thoroughly prevent problems that may occur when winding excessively.

Figures 1 to 4 show an input/output device using a spring as one embodiment of the first invention, of which Figures 1 and 2 show the initial state before input has started, and Figures 3 and 4 show the state just before input has ended and output has started, at which point a malfunction occurs due to overwinding.

As the basis for this configuration, a frame 1 is formed by interposing multiple connecting rods 5, 5, ... between a base side plate 2 and an opposing side plate 3, within which a main spring 7 and a secondary spring 8 that work together for input and output are arranged in parallel to form an input/output device using constant force springs. Of the main and secondary springs 7, 8, the main spring 7 is formed to be slightly long and wide, making it relatively strong. Note that this relatively strong structure may also be achieved by using multiple main springs 7, 7, 7, as will be shown in the embodiment described later (see Figure 5).

An input/output shaft 9 is rotatably supported at the upper end of the frame 1, one end of which protrudes from the base side plate 2 as an input/output end shaft 11. A composite drum 10 is fixedly attached to the input/output shaft 9, and a pair of left and right main and sub winding grooves 11, 12 are integrally formed in the composite drum 10 so that the main spring 7 and sub spring 8 are wound in parallel. In this case, both winding grooves 11, 12 are formed to have the same diameter.

A parallel pair of shafts 15 is installed at the bottom of the frame 1, and a main unwinding drum 17 is supported on the shaft in correspondence with the main winding groove 11 of the composite drum 10, and a sub-unwinding drum 18 is supported on the shaft in correspondence with the sub-winding groove 12 so that they can rotate independently. Both unwinding drums 17, 18 are also formed with the same diameter. In addition, a transmission bolt 22 is attached to the main unwinding drum 17 and the sub-unwinding drum 18, which collide with each other and are engaged, so that they rotate simultaneously due to a fixed rotating lug in both forward and reverse directions. In addition, an annular groove 24 is provided in the main unwinding drum 17 to receive the bolt head.

In the initial position (Figs. 1 and 2), the main and sub springs 7 and 8 are normally wound on the main and sub unwinding drums 17 and 18, respectively. Therefore, elasticity is accumulated by unwinding onto the combined drum 10, but since there is no unwinding, the combined drum 10 is empty, so to speak. Also, since the main and sub springs 7 and 8 have their strengths and weaknesses, at this time, the number of times the sub spring 7 is wound on the sub unwinding drum 18 is relatively small. Naturally, both ends of the two springs 7 and 8 are fixed to the winding grooves 11 and 12 of the combined drum 10, and to the main unwinding drum 17 and the sub unwinding drum 18. 19 indicates the fixing screws.

When the input/output shaft 9 rotates in the winding direction (Pa), the main and sub springs 7, 8 are wound into the combined drum 10 from the main unwinding drum 17 and sub unwinding drum 18 against the elasticity of both of them, but because the springs 7, 8 have different lengths, the short sub spring 8 is pulled all the way to the end and unwinding is completed on the sub unwinding drum 18 on that side (Figures 3 and 4). This is the input completion point, but because elasticity has accumulated in the main and sub springs 7, 8, a rewinding force is generated on the main and sub unwinding drums 17, 18, and this force rotates the input/output shaft 9 in the reverse direction (Pb).

At this point, let us say that there is a problem with the short secondary spring 8 not being able to rewind and return to normal on its own. In other words, let us say that a problem has arisen in which the secondary spring 8 has completed unwinding (overwound) and is therefore unable to rewind on its own. However, even if such a problem has arisen, when a force is applied to rewind the main spring 7, the secondary spring 8 also begins to rewind, and normal rewinding force can be restored.

When the main and sub springs 7, 8 simultaneously elastically return and rewind in this way, the pull causes the main and sub springs 7, 8 to unwind from the main winding groove 11 and sub winding groove 12 of the composite drum 10, and the input and output shafts 9 obtain an output that rotates in the reverse direction (Pb), returning to the initial point shown in Figures 1 and 2. The input and output shafts 9 can then be rotated again to obtain a subsequent output by input operation.

The above is a case where the input and output are achieved by forward and reverse rotation of the same input/output shaft 9, but in the next example (Figure 5), the input shaft 31 and output shaft 32 are separate, with a torque limiter 33 interposed between them. In other words, an embodiment of the second invention will be described, but since it is basically the same as the previous embodiment, the figures corresponding to Figures 3 and 4 will be omitted.

Figure 5 shows an example of the second invention implemented in a part of a certain device, with the case 30 having an opposing side plate 3 spaced apart from the base side plate 2 at one end, a follow-up opposing side plate 4 spaced apart from that, and a further following opposing side plate (not shown). The space between the base side plate 2 and the opposing side plate 3 is called the first space, the space between the opposing side plate 3 and the follow-up opposing side plate 4 is called the second space, and the space between the follow-up opposing side plate 4 and the further following opposing side plate is called the third space.

Between the base side plate 2 and the opposing side plate 3 (first space), an input shaft 31 is installed at the middle of the height, an output shaft 32 is installed at the top, and a parallel pair of shafts 15 are installed at the bottom end, and are rotatably supported by bearings. A driving gear 39 is provided in the third space on the input shaft 31 via a one-way connecting clutch 37 in the second space. A driven gear 45 that meshes with the driving gear 39 is provided in the third space on the output shaft 32 via a torque limiter 33 in the second space. These two gears 39 and 45 form the direction change mechanism 30. When the input shaft 31 is rotated (by the operating disk 47), the output shaft 32 rotates, and if an excessive load is applied between them, the torque limiter 33 blocks the rotational force (the rotational force is not transmitted).

The composite drum 10 is fixedly attached to the output shaft 32, and the rotational force of the input shaft 31 is transmitted to the composite drum 10 via a torque limiter 33. The composite drum 10 has multiple main winding grooves 11, 11, 11 and one sub-winding groove 12 formed integrally therewith.

On the other hand, a composite main unwinding drum 17 having the same number of unwinding grooves 40, 40, 40 corresponding to the main winding grooves 11, 11, 11, and one auxiliary unwinding drum 18 are supported on the parallel pair of shafts 15 so that they can rotate freely independently of each other. The main springs 7, 7, 7 and the auxiliary springs 8 are normally wound on the unwinding grooves 40, 40, 40 of the main unwinding drum 17 and the auxiliary unwinding drum 18, respectively, resulting in constantly wound springs 7a, 8a. As in the previous embodiment, the auxiliary spring 8 is formed slightly shorter, so that unwinding is completed in advance.

1 is a cross-sectional side view of a spring-based input/output device according to the present invention, showing the device at an initial stage immediately prior to input. FIG. 2 is a cross-sectional view of the input/output device using the spring, as viewed from the front at the same point in time as FIG. 13 is a cross-sectional side view of the input/output device using a mainspring, showing the device at the time of overwinding due to input. FIG. FIG. 4 is a cross-sectional view of the input/output device using the spring, as viewed from the side at the same time point as in FIG. 3 . FIG. 11 is a cross-sectional view showing an example of the second invention of the present application.

Explanation of symbols

7 Main spring 8 Secondary spring 7a, 8b Standby winding 9 Input shaft 10 Composite drum 15 Parallel pair of shafts 17 Main unwinding drum 18 Secondary unwinding drum 20 Remaining winding 30 Direction changing mechanism 31 Input shaft 32 Output shaft 33 Torque limiter

Claims (3)

A composite drum with a main winding groove and a sub winding groove for winding the main spring and the sub spring against their elasticity is fixedly attached to an input/output shaft that rotates forward and outputs in reverse. A main unwinding drum and a sub unwinding drum, in which the main spring and the sub spring are always in standby winding, are rotatably supported on a parallel pair of shafts to the input/output shaft. The main and sub springs are wound in standby winding against their elasticity by the forward rotation of the composite drum accompanying the input, and then the main and sub unwinding drums are wound in a reverse direction by the force of returning the main and sub springs to their original state. This input/output device is characterized in that a difference in the length of the remaining winding between the main spring and the sub spring is set so that the sub spring winds up first on the sub unwinding drum, completing the return, and at the same time, there is an unwound portion on the main unwinding drum at that point. The output shaft is connected to the input shaft via a one-way connection clutch that transmits only the force that rotates the output shaft in the forward direction and a direction-changing mechanism that changes the direction of force transmission. A parallel pair of shafts is also connected to the input shaft. A composite drum is fixedly attached to the output shaft, and has a main winding groove and a sub winding groove that winds the main spring and the sub spring against their respective elastic forces. The parallel pair of shafts rotatably support the main unwinding drum and the sub unwinding drum, on which the main spring and the sub spring are always wound in standby. A spring input/output device characterized in that the spring is wound up against elasticity in the main winding groove and the sub winding groove by the forward rotation of the composite drum due to input, and then the force of returning the spring back to the main unwinding drum and the sub unwinding drum produces a reverse rotation torque as an output on the output shaft, and the difference in length between the main spring and the sub spring is set so that the sub spring is unwound first in the sub unwinding drum and completes the return, and at the same time, there is an unwound portion on the main unwinding drum at that point. The spring-based input/output device according to claim 2, characterized in that a torque limiter is interposed between the input shaft and the output shaft to prevent excessive force from being applied to the secondary unwinding drum when the secondary spring is fully unwound due to overwinding of the secondary spring in the composite drum.

Images