JPH0594535U - Universal shaft coupling - Google Patents

Abstract

(57) [Summary] [Purpose] It can be manufactured with synthetic resin, and shock, vibration, lubrication,
(EN) Provided is a universal shaft joint which is free from problems such as dirt and rust, has a simple structure, has a small number of parts, can be easily manufactured and assembled, and has excellent durability and reliability. [Structure] A driven shaft 3a and a drive shaft connecting member 11 in which a connecting portion 16 having an internal space forming a part of a spherical internal space is integrally connected to the tip of a shaft portion 15 connecting the drive shaft 2 and the driven shaft 3a. A freely movable shaft in which a spherical connecting portion 24 is integrally connected to the tip of the shaft portion 23.
12 and the shaft portion 23 of the free movable shaft 12 in a loosely fitted state, and the spherical connecting portion of the free movable shaft 12 in a spherical internal space formed by fitting together with the connecting portion 16 of the drive shaft connecting member 11. A movable shaft holding member 13 into which 24 is fitted, and an elastic member 14 that urges the drive shaft connecting member 11 and the free movable shaft 12 in a linear direction are formed. The engaging protrusions on the outer surface are engaged.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a universal joint, and more specifically, a universal joint for connecting a drive shaft such as a crank handle or a motor to an operating shaft such as a screw shaft in a lifting mechanism for the floor of a medical or home bed. It is about.

[0002]

[Prior Art]

 Most conventional universal joints are made of metal. However, when using a universal shaft joint made of metal, when it is used for a lifting mechanism for the bed of a bed, etc., shock and vibration are likely to occur, it is necessary to lubricate, it is easy to get dirty, and further rust prevention is required. However, there were many difficulties when it was used as a bed, which requires hygiene and quietness. Therefore, a universal shaft joint that can be made of synthetic resin can be used as a universal shaft joint that can be used for a bed or the like by overcoming the above-mentioned difficulties of the metallic universal shaft joint. It is proposed in the Japanese publication.

[0003]

[Problems to be solved by the device]

 However, in the case of the conventional synthetic resin universal shaft joint as described above, the structure is complicated and the number of parts is large, so not only is it time-consuming to manufacture and assemble the parts, but also durability and reliability. In terms of sex, it was not always sufficient.

In view of the above points, the present invention can be manufactured from synthetic resin as a universal shaft joint used for a bed floor elevating mechanism and the like, and there is no problem of shock, vibration, oil supply, dirt, rust, etc. However, the purpose of the present invention is to provide a universal joint that has a simple structure and a small number of parts, can be easily manufactured and assembled, and has excellent durability and reliability.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the universal joint according to the present invention comprises a part of a spherical inner space formed at the tip of a shaft portion that engages a drive shaft in a rotational direction and is movably inserted in the axial direction. A drive shaft connecting member formed by integrally connecting a connecting portion having an internal space, and a spherical connecting portion integrally formed at the tip of the shaft portion that connects with the driven shaft so as to be engageable in the rotational direction. The freely movable shaft and the shaft portion of the freely movable shaft are loosely fitted to each other, and are fitted to the connecting portion of the drive shaft connecting member to form a spherical internal space to form the spherical internal space. A movable shaft holding member into which the spherical connecting portion of the movable shaft is fitted, and an elastic member which is inserted in the axial direction of the drive shaft connecting member and the freely movable shaft to urge the two in a linear state. And the movable shaft holding member and the connecting portion of the drive shaft connecting member To form a long groove portion in a direction, slidably summarized in that obtained by forming an engaging projection which engages in said groove on the outer surface of the spherical connection portion movably axis.

[0006]

[Action]

 The structure of the universal shaft joint according to the present invention is as described above, and the spherical joint portion of the universal movable shaft is fitted in the spherical internal space formed by the drive shaft connecting member and the movable shaft holding member to drive the drive shaft. A state in which the connecting member and the freely movable shaft are flexibly connected, and the engaging protrusion of the freely movable shaft engages with the groove of the spherical inner space so that both can be engaged in the rotational direction. The drive shaft and the driven shaft, which are connected to the drive shaft connecting member and the freely movable shaft so as to be engageable in the rotational direction, are connected to the drive shaft connecting member and the self-movable shaft. The parts are connected so as to be bendable and engageable in the rotational direction, and thus the rotation of the drive shaft is transmitted to the driven shaft by the universal shaft joint.

[0007]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment in which the universal joint according to the present invention is used in a bed floor lifting mechanism of a bed. Reference numeral 1 in the drawing denotes a universal joint according to the present invention, and 2 indicates A drive shaft, 3 is an actuator, 4 is a crank handle attached to the drive shaft, 5 is a mounting member for a bed or the like, 6 is a shaft cover, and 7 is a mounting screw.

The universal joint 1 is composed of a drive shaft connecting member 11, a freely movable shaft 12, a movable shaft holding member 13, and a spring 14 as an elastic member. The drive shaft connecting member 11 is made of a hard synthetic resin, and is integrally connected to a distal end of a cylindrical shaft portion 15 that engages with the drive shaft 2 in the rotational direction and is movably inserted in the axial direction. And a connecting portion 16 having an internal space that constitutes a part of the spherical internal space, and a rotation stopping piece 17 attached to the tip of the drive shaft 2 by a fixing pin 20 is slid in the axial direction on the inner surface of the shaft portion 15. By forming an axial vertical groove 18 that freely engages, it engages with the drive shaft 2 in the rotational direction and is inserted so as to be movable in the axial direction, and is connected by a pin 21 in a retaining state. Become. Next, the freely movable shaft 12 is similarly made of a hard synthetic resin, and the male screw 3a of the actuator 3, which is a driven shaft, is inserted and connected by a fixing pin 22 in a state of being engaged in the rotational direction. A spherical connecting portion 24 is integrally connected to the tip of the shaft portion 23. The movable shaft holding member 13 is similarly made of a hard synthetic resin, and is fitted onto the shaft portion 23 of the free movable shaft 12 in a loosely fitted state, and also fitted to the drive shaft connecting member 11. Then, a spherical internal space 25 into which the spherical connecting portion 24 of the freely movable shaft 12 is fitted is configured together with the drive shaft connecting member 11. On the inner surface of the spherical internal space 25, there are provided four axially long grooves 26 ... At the same time, the spherical connecting portion 24 of the freely movable shaft 12 is slidably engaged in the groove 26. The flattened cylindrical engaging protrusions 27 ...

An assembling procedure of the universal joint 1 according to the present invention will be described with reference to FIG. First, the drive shaft 2 is inserted from the side of the connecting portion 16 at the tip of the drive shaft connecting member 11, the rotation stopping piece 17 at the end of the driving shaft 2 is engaged with the vertical groove 18 in the shaft portion 15, and the retaining pin 21 is provided. By attaching the drive shaft 2, the drive shaft 2 is engaged with the drive shaft connecting member 11 in the rotational direction and is movably connected in the axial direction. On the other hand, the male screw 3a of the actuator is inserted into the mounting member 5, the thrust bearing 28, and the movable shaft holding member 13, and then inserted into the shaft portion 23 of the freely movable shaft 12, and both are engaged in the rotating direction by the fixed pin 23. Connect in a combined state. Then, with the spring 14 interposed between the drive shaft connecting member 11 and the freely movable shaft 12, the spherical connecting portion 24 at the tip of the freely movable shaft 12 is inserted into the connecting portion 16 at the tip of the drive shaft connecting member 11. After the insertion, the movable shaft holding member 13 externally fitted to the movable shaft 12 is fitted to the connecting portion 16 of the drive shaft connecting member 11 to form the connecting portion 16 and the movable shaft holding member 13. The spherical connecting portion 24 of the freely movable shaft 12 is fitted in the spherical internal space 25 so that the engaging projection 27 provided on the spherical connecting portion 24 is engaged with the groove portion 26 formed in the spherical internal space 25. To meet.

In the universal joint 1 of the present invention as described above, the spherical connecting portion 24 of the free movable shaft 12 is fitted in the spherical inner space 25 formed by the drive shaft connecting member 11 and the movable shaft holding member 13. By doing so, the drive shaft connecting member 11 and the free movable shaft 12 are flexibly connected, and the engaging protrusion 27 of the free movable shaft 12 engages with the groove 26 in the spherical inner space 25. Thus, the drive shaft connecting member 11 and the freely movable shaft 12 are engaged with each other in the rotational direction, and are connected to the drive shaft connecting member 11 and the freely movable shaft 12 so as to be engaged with each other in the rotational direction. The drive shaft 2 and the male screw 3a of the actuator are connected via the universal shaft coupling 1 so as to be bendable and engageable in the rotational direction, so that the rotation of the drive shaft 2 by the crank handle 4 causes the actuator shaft to rotate. It is transmitted to the screw 3a. Further, the spring 14 interposed between the drive shaft connecting member 11 and the freely movable shaft 12 elastically biases the drive shaft connecting member 11 and the freely movable shaft 12 in a direction in which they are always in a linear state, thereby bending By making the drive shaft 2 and the male screw 3a of the actuator always return to the linear state, the rotation of the drive shaft 2 to the male screw 3 of the actuator can be smoothly transmitted.

According to the universal joint 1 according to the present invention as described above, the universal movable shaft 12 is formed in the spherical inner space 25 constituted by the movable shaft holding member 13 and the drive shaft connecting member 11 that connects the drive shaft 2. The spherical connecting portion 24 of the spherical connecting portion 24 is fitted inside to connect the both, and the engaging projection 27 of the spherical connecting portion 24 is engaged with the groove portion 26 of the inner surface of the spherical inner space 25 so that both are engaged in the rotational direction. Due to its extremely simple structure, the universal joint 1 can be easily made of synthetic resin, etc. By making it of synthetic resin in this way, shock, vibration, rust, etc. occur. It can be used for bed floor lifting mechanism, etc. without any fear and no problem of dirt due to refueling. Moreover, the drive shaft 2 is connected to the shaft portion 15 of the drive shaft connecting member 11 so as to be movable in the axial direction, so that the crank handle 4 does not become an obstacle in the bed floor lifting mechanism when not in use. Even when the structure is such that the drive shaft 2 can be stored in a pushed state, the crank handle 4 and the drive shaft 2 are movably connected as in the case of using a conventional universal joint. There is no need to fix the crank handle 4 directly to the drive shaft 2 with screws 41 or the like, and the structure is simple and the number of parts is small.

In the universal joint 1 of the illustrated example, the engaging projections 27 and the groove portions 26 are provided at four locations, that is, the spherical connecting portion 24 of the free movable shaft 12 and the spherical internal space 25 in which the spherical connecting portion 24 is fitted. However, the numbers of the engaging protrusions 27 and the groove portions 26 are not particularly limited, and the drive shaft connecting member 11 and the freely movable shaft 12 may be non-rotatably connected by the engagement of both. In order to allow both to bend freely, it is desirable to provide them at four places as in the embodiment. Further, in the embodiment, the spring 14 is used as the elastic member for urging the drive shaft connecting member 11 and the freely movable shaft 12 so as to be in a linear state. However, instead of the spring 14, synthetic rubber, synthetic resin, etc. It is also possible to use a rod-shaped elastic member or the like made in.

Further, the crank handle 4 of the illustrated example is capable of undulating in a direction orthogonal to the axial direction and a direction parallel to the axial direction at the tip of the crank arm 42 fixed orthogonally to the axial direction of the drive shaft 2. The handle shaft 43 is attached by a pin 46, the handle 44 is rotatably attached to the handle shaft 43, and when the handle 44 is folded in a direction orthogonal to the axial direction, a recess provided on the outer surface of the crank arm 42 is provided. It can be stored in 45. In the figure, reference numeral 47 is a spring for holding the handle 44 in the up and down state, and reference numerals 48 and 49 are numbers attached to the crank arm 42 and the handle 44.

Furthermore, since the drive shaft 2 is attached to the drive shaft connecting member 11 so as to be movable in the axial direction, the crank handle 4 at the tip of the drive shaft 2 is mounted when not in use. It is pushed in the direction of the drive shaft 2 so as not to get in the way. In this case, as shown in Fig. 10 and below, a catch for holding the crank handle 4 on the channel member 50 such as the rear frame of the bed. By providing 51, it is possible to securely store the crank handle 4 in the pushed-in state. The catch 51 is made of synthetic resin or the like, and in the example shown in the figure, a pair of elastic holding pieces 53, 53 are provided side by side with the insertion hole 52 through which the drive shaft 2 is inserted. A groove 54 is formed, and a fitting protrusion 55 that is fitted into the fitting groove 54 is formed on the back surface of the crank arm 42 of the crank handle 4. The crank handle 4 is pushed in the direction of the drive shaft 2 and cranked. The fitting protrusion 55 on the rear surface of the arm 42 is fitted into the fitting groove 54 of the catch 51 and fixed by the pair of sandwiching pieces 53, 53, and the handle 44 is further folded to fit in the recess 45 of the crank arm 42. The crank handle 4 can be stored without hindering it by putting it in the storage state, and by preventing the crank handle 4 from rotating during storage, the floor of the bed may be inadvertently moved up and down. Nor.

[0016]

[Effect of the device]

 As described above, according to the universal joint according to the present invention, the structure is simpler than the conventional universal joint, the number of parts is small, and the manufacturing and assembling are easy. By making it, there is no risk of shock, vibration, dirt, rust, etc. like metal universal shaft joints, and it is hygienic and quiet, making it suitable for a bed lifting mechanism, etc. It can be used.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a bed floor elevating mechanism using a universal joint according to the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is also a vertical side view.

FIG. 4 is a transverse plan view of the same.

5 is a sectional view taken along line AA in FIG.

FIG. 6 is a sectional view taken along line B-B of FIG.

7 is a cross-sectional view taken along line CC of FIG.

FIG. 8 is a sectional view taken along line D-D of FIG.

FIG. 9 is a DD cross-sectional view showing a state in which the drive shaft connecting member and the freely movable shaft are also bent.

FIG. 10 is a perspective view of essential parts showing the relationship between the crank handle and the catch.

FIG. 11 is a perspective view of a crank handle held by a catch.

FIG. 12 is a partial cross-sectional plan view showing the relationship between the crank handle and the catch.

13 is a sectional view taken along line EE in FIG. 12.

[Explanation of symbols]

 1 Universal shaft joint 2 Drive shaft 3 Actuator 3a Male screw 4 Crank handle 11 Drive shaft connecting member 12 Free movable shaft 13 Movable shaft holding member 14 Spring 15 Shaft part 16 Connecting part 23 Shaft part 24 Spherical connecting part 25 Spherical internal space 26 Groove part 27 Engagement protrusion

Claims (1)

[Scope of utility model registration request] 1. A connecting portion having an internal space forming a part of a spherical internal space is integrally connected to a tip of a shaft portion that engages a drive shaft in a rotational direction and is movably inserted in the axial direction. A drive shaft connecting member, a free movable shaft in which a spherical connecting portion is integrally connected to the tip of a shaft portion that is engageable with the driven shaft in the rotational direction, and a shaft portion of the free movable shaft. A movable shaft retainer which is fitted externally in a loosely fitted state and is fitted to the connecting portion of the drive shaft connecting member to form a spherical internal space, and the spherical connecting portion of the free movable shaft is internally fitted in the spherical internal space. A member and an elastic member that is inserted in the drive shaft connecting member and the freely movable shaft in the axial direction to urge the two in a linear state, and the connecting portion of the drive shaft connecting member and the movable shaft holding member. A groove that is long in the axial direction is formed in the spherical internal space that is composed of Universal coupling, characterized in that by forming a engaging protrusion to slidably engage in said grooves on the outer surface of the spherical connecting portion of the shaft.