Patent Application
20100287729
This application claims priority based on Chinese Patent Application No. 2009203031951, filed on May 15, 2009.
The present invention relates to the field of door closers. In particular, to door closers of the type including a hydraulic damper.
A door closer is a device that allows a door to slowly close automatically. In situations when the door is blown open by wind, the presence of the door closer can effectively lower the impacting sound of the door being shut closing and, to some degree, protect the door.
One prior door closer is disclosed in a Chinese Patent Application No. 20061026679.4. Such prior door closer is of the type which has a thin integrated enclosure which is designed to have a sealer with a cylinder hole on at least one of its sides. A piston is connected to a compressing spring and positioned in the cylinder hole. The piston has a gear with a drive pinion on a drive shaft which is in a block-shaped shaft housing. The shaft housing is supported on two opposite sides of the enclosure with a bearing and is also sealed with a bearing housing through a sealing system. The drive shaft extends from the two housings such that the drive shaft can be connected to a connection rod or a drive arm. The enclosure has a circumferential area when view from one end. Such circumferential area forms a beginning at a posterior wall of the enclosure and an end at a front surface. The front surface is configured to extend parallel to the posterior wall. In addition, the enclosure has a protruding fixing knob and the posterior wall has a fixing hole on its side.
Such prior door closers have structures which are difficult to assemble, are expensive to manufacture, are difficult to use and are not-stable due to their complicated structure.
It is an object of the invention to provide an improved door closer which overcomes the problems and shortcomings of the prior art, including those referred to above.
Another object of the invention is to provide an improved hydraulic door closer which is of a simple structure.
Another object of the invention is to provide an improved hydraulic door closer which is easy to assemble.
Still another object of the invention is to provide an improved hydraulic door closer which has a low production cost.
Yet another object of the invention is to provide an improved hydraulic door closer which allows for retention of a door at any desired angle or position in its path.
How these and other objects are accomplished will become apparent from the following description and the drawings.
The present invention relates to a hydraulic door closer of the type including an elongated housing having a closed end and an opposite apertured end which defines an aperture therethrough. A connection rod extends through the aperture into the housing. A piston is secured at an inner end of the connection rod within the housing. A spring is positioned within the housing about the connection rod and extends between the apertured end and the piston. The piston divides the housing into a closed-end chamber and an apertured-end chamber. An external part or portion of the connection rod extends outside the housing.
The door closer disclosed herein includes a throttle valve and a check valve. The throttle valve is formed in the piston and defines a throttle-valve fluid passage which is configured to be open for passing a fluid between the chambers and closed to isolate the chambers. The check valve is formed in the piston and defines a check-valve fluid passage between the chambers. The check-valve fluid passage is larger than the throttle-valve fluid passage. It is highly preferred that, during door opening, both valves are open for fluid passage therethrough while, during door closing, the check valve is closed for restricted fluid flow only through the throttle valve to slow the door motion. As a result, the door closer allows the door to close slowly with the damping action of hydraulic fluid or hydraulic oil which lowers the impact sound in closing of the panel to effectively protect the panel.
Preferred embodiments of the inventive door closer have a stopping/holding mechanism. The stopping/holding mechanism includes a piston groove, a rod groove and a positioning pin disposed between the piston and the connection rod. The piston groove is formed in the piston for retaining the entire positioning pin during door opening/closing motion. The rod groove is formed in the connection rod and is configured to receive a portion of the positioning pin. The piston groove and the rod groove form limit grooves which facilitate holding of the door in the desired position. The door stops when the piston groove and the rod groove are moved into alignment with each other. Specifically, door movement stops when preferably approximately one-half of the positioning pin is within the rod groove and the other half is within the piston groove to retain the grooves in alignment. Such action closes both the check valve and the throttle valve and blocks the fluid flow between the chambers, thus stopping the movement of the door and holding the door at the desired position.
In some preferred embodiments, the piston includes a valve body and a spring-supporting portion. Such structure facilitates placement of the throttle and check valves by using their respective structures and to simplify the overall structure of the door closer. The inner end of the connection rod extends through the spring-supporting portion. The check valve is preferably formed in the valve body. The throttle valve is preferably formed between the valve body and the spring-supporting portion.
In one preferred embodiment, the piston groove of the stopping/holding mechanism is formed in the spring-supporting portion of the piston.
In some preferred embodiments, a central portion of the valve body defines a through throttle bore which connects the closed-end and apertured-end chambers of the housing. The throttle bore preferably includes a cone-shaped end cavity near the spring-supporting portion of the piston. The connection rod preferably includes a cone-shaped rod-section at its inner end which extends through the throttle bore. The inner end of the connection rod preferably cooperates with the throttle bore to form the throttle-valve passage. The flow of hydraulic oil can be cut-off or stopped at the throttle valve through the cooperation between the cone-shaped rod-section and the cone-shaped end cavity to hold the door closer at a certain position with the door panel being partially open.
When it is necessary to stop the door in a partially open position during closing or opening of the door, the user provides a slight push in the closing direction on the door itself. The cooperation of the hydraulic sealing between the cone-shaped end cavity with the cone-shaped rod-section will close the throttle valve and stop the flow of hydraulic oil. The interaction between the limit grooves and the positioning pin ensures that the throttle valve reliably cuts the hydraulic-oil flow to keep the door panel stable at the desired opened position. This facilitates holding of the door partially open when necessary. To close the door, the user just needs to push the door panel slightly in the opening direction.
The inner end of the connection rod preferably includes a threaded portion connected to a regulating nut. The cone-shaped end cavity of the throttle bore is between the regulating nut and the cone-shaped rod-section of the connection rod. It is preferred that the throttle bore includes a nut-receiving cavity which is opposite to the cone-shaped end cavity. The regulating nut may be positioned within the nut-receiving cavity. The axial position of the regulating nut on the connection rod may be changed by rotating the regulating nut to adjust the closing speed of the door closer by changing the relative axial position between the cone-shaped end cavity of the throttle passage and the cone-shaped rod-section on the connection rod. The placement of the regulating nut in the nut-receiving cavity of the throttle bore substantially improves structural compactness of the piston to ensure stability of the regulating nut on the axial position of the connection rod.
The check valve preferably includes the check-valve passage and a plug configured for closing the passage to fluid flow through the check valve. The check-valve passage is preferably formed by a check-valve cavity and a side passage. The check-valve cavity includes a closeable side and is preferably formed within the valve body such that the check-valve cavity is in communication with both the closed-end chamber and the apertured-end chamber. The side passage is preferably formed between the valve body and an inner surface of the housing such that the inner surface of the housing may form a part of the check valve. The side passage is in communication with the check-valve cavity. The plug is preferably positioned within the check-valve cavity for sliding against its closeable side to block the flow of the fluid through the check valve. It is preferred that the plug has a substantially round cross-section and that the closeable side of the check-valve cavity has an arch-shaped surface.
In preferred embodiments, the check-valve cavity is a sliding cavity within the valve body, and the plug is a slider positioned within the cavity. The end of the cavity extends into the leading side of a main flow path. The slider, sliding cavity, and the inner side of the housing form the check valve. The slider and the sliding cavity form the main component of the check valve, which simplifies the structure of the check valve and facilitates the placement. The above-mentioned slider may be a ball bearing, and the leading side is arc-shaped. The space between the ball-bearing-shaped slider and the arc preferably cooperate for improved hydraulic sealing to improve the operation stability of the check valve.
In operation, the two chambers of the housing should be fully filled with a hydraulic oil. The door closer is secured to a back side of the door panel through connection of one end of the housing, and the external end of the connection rod to the door frame. Opening of the door panel drives the connection rod and the piston within the housing. In the opening process, the spring is compressed and stores certain elastic potential. At such time, the check valve opens and the hydraulic oil flows between chambers of the housing. When the door panel receives the elastic potential released from the spring, such potential draws the piston in a reverse direction. Such piston movement results in the hydraulic oil also flowing back. Due to such flow, the check valve shuts closed such that the hydraulic oil flows only through the throttle valve. Because the throttle valve has the fluid passage which is of substantially small cross-section dimension, the hydraulic oil flows in a small volume and forms a resistance to the spring release. This controls the closing speed of the door panel.
In order that the advantages of the invention will be readily understood, a more detailed description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:
One preferred embodiment of door closer 100 includes a throttle valve 21 and a check valve 22. Throttle valve 21 is formed in piston 20 and defines a throttle-valve fluid passage 3 which is configured to be open (
Piston 20 includes a valve body 6 and a spring-supporting portion 7. It is seen in
A central portion 24 of valve body 6 defines a throttle bore 25 which connects closed-end chamber 15 and apertured-end chamber 16 of housing 1. Throttle bore 25 includes a cone-shaped end cavity 26 near spring-supporting portion 7 of piston 20. Connection rod 10 includes a cone-shaped rod-section 42 at its inner end 40 which extends through throttle bore 25. As further seen in
Inner end 40 of connection rod 10 includes a threaded portion which is connected to regulating nut 12. As seen in
Check valve 22 includes check-valve passage 23 and a plug 4 configured for closing passage 23 to the fluid flow through check valve 22. Check-valve passage 23 is formed by a check-valve cavity 2 and a side passage 17. Check-valve cavity 2 includes a closeable side 5 and is formed within valve body 6 such that check-valve cavity 2 is in communication with both closed-end chamber 15 and apertured-end chamber 16. Check-valve cavity 2 has a curved configuration with the main flowing side extending to closeable side 5 near spring-supporting portion 7. Plug 4 is positioned inside check-valve cavity 2 for sliding movement therealong. When plug 4 approaches closeable side 5 and inner surface 33 of housing 1 under the driving of hydraulic oil, check valve 22 is closed for hydraulic-oil flow therethrough.
Side passage 17 is formed between valve body 6 and an inner surface 33 of housing 1 such that inner surface 33 forms a part of check valve 22. Side passage 17 is in communication with check-valve cavity 2. Plug 4 is positioned within check-valve cavity 2 for sliding against its closeable side 5 to block the fluid flow through check valve 22. Plug 4 has a substantially round cross-section and closeable side 5 of check-valve cavity 2 has an arch-shaped surface.
As shown in
To achieve stopping and holding of door 50 in a partially-open position during closing or opening of door 50, one needs to just slightly push door 50 in closing direction 52. When the action is made, relative axial motion will occur between connection rod 10 and valve body 6. Cone-shaped rod portion 42 of connection rod 10 will close cone-shaped end-cavity 26 of throttle bore 25 to cut the flow of the hydraulic oil through throttle valve 21. Such action will move rod groove 9 and piston groove 14 into alignment and, as shown in
To close door panel 50 held at a certain opening position, one just needs to push door 50 slightly in the opening direction 51. Cone-shaped rod section 42 will retreat from cone-shaped end cavity 26 to form a clearance for the hydraulic oil to flow through. At the same time, positioning pin 8 will receive a shearing force under which it can be fully pushed back into piston groove 14 of spring supporting portion 7. In this way, the hydraulic oil compressed in closed-end chamber 15 can flow back into apertured-end chamber 16 through throttle valve 21. Piston 7 under the action of spring 11 moves toward closed end 30 to close door 50.
To continue opening door 50 when it is held partially open, one just needs to open door 50 directly without doing any other actions.
Reference throughout this specification to “one embodiment,” “an embodiment,” “a preferred embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” “in a preferred embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.
While the present invention has been described in connection with certain exemplary or specific embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications, alternatives, modifications and equivalent arrangements as will be apparent to those skilled in the art. Any such changes, modifications, alternatives, modifications, equivalents and the like may be made without departing from the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009203031951 | May 2009 | CN | national |
