Telescoping rod structure for linear actuator

A telescoping rod structure, for a linear actuator, arranged at a connecting position of a telescoping rod of a linear actuator, mainly includes a telescoping rod, a sleeve, and a connecting cap, wherein the telescoping rod is connected to a linear transmitting mechanism, and an accommodating groove passing through the telescoping rod is arranged at top of the telescoping rod; furthermore, the sleeve, arranged in the accommodating groove, is a hollow pipe piece for accommodating a connecting element to pass through; finally, the cap is a hollow lid body, the peripheral of which is arranged a plurality of corresponding projecting seats, at each of which a thorough hole is arranged such that, when the cap is fitted onto the top of the telescoping rod, it may fix the position of the sleeve arranged at the accommodating groove, in the meantime, by making the thorough holes just correspond to the hollow position of the sleeve, it being able to facilitate the connecting element to be fitted and connected securely therein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a linear transmission mechanism, in particular, to a telescoping rod of a linear actuator.

2. Description of Prior Art

The linear transmission mechanism commonly seen in current market, for example, linear actuator, is a kind of assembly driven by motor, gear set, and connecting rod, etc., wherein a lead screw is brought along to rotate by the power generated from the motor, so that it may facilitate a telescoping rod generating an telescoping action in linear direction, by which other assembly connected to the telescoping rod may generate pushing and pulling actions, which are generally seen in our daily lives, for example, a patient bed moved vertically and a mini-elevator loaded with objects, which are all application examples of linear transmission mechanism.

In particular, the telescoping rod is one critical component to be connected to other assemblies, and the stability of the connecting structure of the telescoping rod will directly influence the pushing and pulling actions to be brought along and generated smoothly. As shown inFIG. 1, according to a prior structure, a universal joint102is screwed on top of a telescoping rod101and has an accommodating groove103penetrating the main body thereof for facilitating a connecting element to be accommodated in the accommodating groove103, whereby a connecting relationship between the telescoping rod101and other assemblies may be secured. However, since of the high cost of the universal joint102, its inventory cost is relatively high for manufacturers.

As shown inFIG. 2, according to another prior structure, an accommodating groove103is directly disposed at the rod head of a telescoping rod101, and a sleeve104arranged in the accommodating groove103ais tightly fitted and connected therein for facilitating a connecting element to be arranged in the sleeve104. Although this structure may lower down the cost significantly, it is difficult to install other sleeve104with different outer radius in any time. Once a sleeve104is tightly fitted into the accommodating groove103a, the linear transmission mechanism can only be matched with a connecting element with an outer radius same as the inner radius of the sleeve104, thus causing an inconvenient usage. Furthermore, it is easy to make the sleeve104generate wearing deformation and dropped off after long usage, so there is a worrisome on structural security as well.

As shown inFIG. 3, a further prior structure is to arrange a radial accommodating groove103aat the position of the rod head of a connecting rod, and a sleeve105is formed and secured in the accommodating groove103aby means of powder-pressing process, whereby the drawback of easy wearing and deformation according to aforementioned structure that is constructed by tight fitness may be avoided. However, this kind of method still has the difficulty to install other connecting element with different radial size. Furthermore, since the sleeve105is made of powder material under a powder-pressing process of high temperature and high pressure, its structure is easily squeezed to incur smashing phenomenon, which is dangerous to the connected structure in terms of safety and stability.

Therefore, under the considerations of structural safety and the convenience of changing parts besides cost expense, it is indispensable to perceive a solution to overcome the drawbacks of prior arts.

SUMMARY OF THE INVENTION

Aiming to solve aforementioned drawbacks, the main objective of the invention is to provide a telescoping rod's structure, for a linear actuator, capable of applying a cap to hold a sleeve with variable inner radius and, since of the application of the detachable connecting cap arranged at top of the telescoping rod, not only the position of the sleeve arranged in the interior of the telescoping rod may be held, but also other sleeves with different inner radiuses but same outer radius may be interchanged. Because the cap can be detached, the limitations of inventory's preparation and cost can be reduced significantly.

In order to achieve aforementioned objectives, the invention is to provide a telescoping rod's structure for a linear actuator, mainly consisting of a telescoping rod, a sleeve, and a connecting cap, wherein the telescoping rod is connected to a linear transmission mechanism, and an accommodating groove passing through the telescoping rod is arranged at top of the telescoping rod; furthermore, the sleeve, arranged in the accommodating groove, is a hollow pipe piece for accommodating a connecting element to pass through; finally, the cap is a hollow lid body, the peripheral of which is arranged a plurality of corresponding projecting seats, at each of which a through hole is arranged such that, when the cap is fitted onto the top of the telescoping rod, it may fix the position of the sleeve arranged at the accommodating groove, in the meantime, by making the through holes just correspond to the hollow position of the sleeve, it being able to facilitate the connecting element to be fitted and connected securely therein.

DETAILED DESCRIPTION OF THE INVENTION

Please refer toFIG. 4andFIG. 5, which respectively are a perspective structural illustration and a perspective enlarging view of local structure of an embodiment according to the present invention. As shown inFIG. 4, a telescoping rod's structure according to the present invention is arranged at top of a telescoping rod11of a linear actuator1, and its perspective enlarging illustration is shown inFIG. 5. Please further refer toFIG. 6, which is a perspective structural explosive view of the embodiment according to the present invention inFIG. 5, and the telescoping rod's structure mainly comprises a telescoping rod11, a sleeve2, and a connecting cap3, wherein the telescoping rod11is a hollow pipe body, on the wall surface of which a plurality of through holes are arranged corresponding to each other to form an accommodating groove111, which penetrates the main body of the telescoping rod11in radial direction and is arranged below the top of the telescoping rod11for accommodating the sleeve2; furthermore, the sleeve2, the outer surface of which is just tightly arranged in the accommodating groove111, is a hollow pipe body to be fitted with a connecting element; finally, the interior of the connecting cap3is a hollow body, which houses the top of the telescoping rod11and is tightly fitted thereon, and the peripheral of which arranges at least one projecting seat31. In this embodiment, a plurality of corresponding projecting seat31and31aare arranged, and the wall surface of the cap3is arranged at least one through hole311, the position of which just corresponds to the position of the projecting seat31. In this embodiment, the cap3is arranged a plurality of through holes311and311a, both of which respectively correspond to the projecting seat31and31a.

Please refer toFIG. 7, which is a cross-sectional view of the assembled structure of the embodiment according to the present invention inFIG. 5. After the connecting cap3being fitted onto the top of the telescoping rod11, the peripheral edge of the cap3just covers the radial accommodating groove111arranged on the telescoping rod11in a way, such that the sleeve2in the accommodating groove111is fixed therein, making the sleeve2unable to be moved horizontally or even dropped off, because of the operation of the linear actuator. In the meantime, the positions of the projecting seats31,31aare adjusted corresponding to the position of the radial accommodating groove111, making the through holes311,311aarranged at the projecting seats31,31arespectively corresponding to the positions of two side openings of the sleeve2. In this embodiment, the radiuses of the through holes311,311aare substantially equal to the inner radius of the sleeve2, so that it may facilitate the sleeve2to accommodate a connecting element with same radius.

In addition, as shown inFIG. 8, the cap3is also capable of holding a sleeve2with same outer radius but with different inner radius. In this embodiment, the inner radius of the sleeve2ais substantially smaller than the radiuses of the through holes311,311aarranged at the peripheral of the cap1. Thereby, in cooperation with the detachable cap3, it may provide a number of sleeves2with different inner radiuses to be assembled on the telescoping rod11, which facilitates inventory preparation and parts exchange, and thus the inventory cost may be lowered down significantly.

Aforementioned structures are only preferable embodiments of the present invention, being not used to limit its executing scope. Any equivalent variation and modification made according to appended claims is all covered by the claims claimed by the present invention.