AU622255B2 - Speed controller for door-closer - Google Patents

Description

i i r, a i~ i 62225 S F Ref: 116736 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class Complete Specification Lodged: Accepted: Published: Priority: Related Art: 00 r 00 0 0r t #00 00 Name and Address of Applicant: Miwa Lock Kabushiki Kaisha 1-12, Shiba 3-chome Minato-ku Tokyo-to

JAPAN

Address for Service: Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia :i r i; i

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;r 0 00 0 0 r 00 0 tO S 0 0 0 $C CCr Complete Specification for the invention entitled: Speed Controller for Door-Closer The following statement is a full description of this invention, including the best method of performing it known to me/us 5845/4 ABSTRACT OF THE DISCLOSURE: A speed controller for a door closer of the type comprising a cylinder which is filled with a working oil and whose both ends are liquid-tightly closed with cylinder caps; a piston which is inserted into said cylinder for the reciprocal movement in the axial direction of said cylinder, is normally biased in one direction under the force of a bias spring and is formed with a rack extended in the axial direction of said cylinder, a pinion shaft which is rotatably supported by said cylinder and is extended in the direction perpendicular to the axis of said cylinder in such a way that at least one end of said pinion shaft is extended outwardly beyond the wall of said cylinder and whose portion inside said cylinder is formed with a pinion in mesh with said rack of said piston; and an orifice defined in an oil passage intercommunicating between a high-pressure space which is defined by one of said cylinder caps and the front surface of said piston and in which the pressure is increased in re- 00 00 o o° sponse to the displacement of said piston when a door is o o 20 closed and a low-pressure space in which is disposed said bias :0 spring for normally biasing said piston in said one direction, CHARACTERIZED by comprising a communication passage extended from said front surface of said piston to the rear surface thereof in the axial direction of said cylinder; a check valve disposed at one end of said communication passage which is opened at said high-pressure space; and a release pin which is extended inwardly in the axial direction of said cylinder from said cylinder cap on the side of said high-pressure space and in opposing relationship with said front surface of said piston through said high-pressure space in such a way that the leading end of said release pin can partially interfere with the locus of the displacement of said valve body of said check valve and the position of said releasing pin in the axial direction of said cylinder can be adjusted.

4-4w TITLE OF THE INVENTION: SPEED CONTROLLER FOR DOOR CLOSER BACKGROUND OF THE INVENTION: The present invention relates to a speed controller for a door closer for increasing the speed of a door during the end stroke of the closing door in order to improve the engagement of a latch bolt and more particularly a speed controller for a door closer which can permit the easy adjustment of the time at which the latching action is started.

The conventional door closer of the type which closes a door under the force of a spring damped by an oil damper in response to the speed of the closing of the door cannot always assure the satisfactory action of a latch bolt. Furthermore the conventional door closer stops its door closing action Sbefore the latch bolt is completely engaged without completely closing the door when the door closer is attached to an airtight door for a door opening frame of an air-tight room whose side edges are attached with packings against which the stiles r I and rails of the door are forcibly pressed so as to maintain the air-tightness of the air-tight room.

In order to solve such problems, a door closer -s 2 5 4:sloe n5 p_;os til "tyZ Me :Publicatioen No. 3332P/i979.

This door closer is so designed and constructed that it causes i the so-called latching action for engaging the latch bolt by utilizing the inertia force resulting from the increasing the j 3 door closing speed during the end stroke of the closing the door.

More particularly, in the case of the above-mentioned door closer, in order to produce the latching action, a cylinder cap which is in opposing relationship of the leading front end surface of a piston when the door is closed has a bypass passage which is defined in parallel with an orifice 0' ArQ 2 and communicates between the high pressure space and the low pressure space in a cylinder and a check valve in the form of a ball-shaped valve body is disposed at the opening on the high pressure space side of the bypass passage. Furthermore, a pin is extended from the leading front surface cf the piston so that almost at the end of the door closing action, the pin causes the valve body to be removed from its valve seat. As a result, almost at the end of the door closing action, the bypass passage extended in parallel with the orifice is opened so that the damping action becomes ineffective and as a consequence the door closing speed is increased, thereby ensure the positive latching action.

However, in general, there exists no one-to-one correspondence between the position of the piston within the cylinder and the opening angle of the door. That is, there 0 o 0 is no relationship that when the piston reaches a predeter- S mined position or the door is opened by a predetermined angle, 0 a 0 0 the door is opened by a predetermined angle or the piston 0. J0 stops at a predetermined position. As a result, the relation- 4 ship between the position of the piston and the degree of opentil ing of the door varies in many ways depending on the position at which the cylinder is installed, the length of a main arm connected to a pinion shaft of the cylinder, the length of a fork arm whose one end is connected to the leading end of the main arm like a link and the position at which is installed an arm bracket which is normally securely attached to the door frame and rotatably supports the other end of the fork arm.

Meanwhile in order to avoid a danger that the latching action starts while one or more fingers are caught between the door and the door frame, it is preferable that the time when the latching action starts is set immediately after no space is left between the free side stile of the door and the door frame. To this end, in the case of the door closer of the type capable of the latching action described above, the 00 e 0 0 0 0 I o 0 0 0 0 3 latching action actuating time is adjusted by increasing or decreasing the length of the fork arm after the door closer has been installed.

More particularly, the other end of a bar-like member which has an internally threaded hole extended in the axial direction and one end of a bar-like member which is externally threaded are threadably engaged with each other, thereby constructing a fork arm. A pin which rotatably interconnects between one end of the fork arm thus constructed and the leading end of the main arm is pulled out to free the form arm and then the length of the fork arm is increased or'decreased by rotating the one end of the fork arm. Thereafter the leading end of the main arm and the one end of the fork arm are interconnected and then the operation of the door closer is checked. The above-described adjustment procedure is repeated until a satisfactory latching action actuating time is set.

However, the adjustment of the latching action actuating time of the type described above is very complicated and cumbersome and cannot be satisfactorily accomplished by an unskilled man.

SUMMARY OF THE INVENTION: In view of the above, the primary object of the present invention is to provide a door closer whose latching action actuating time can be 20 adjusted in a very simple manner.

This invention in one broad form provides a door closer comprising a cylinder filled with a working fluid and whose both ends are closed in liquid-tight manner by cylinder caps, a piston within said cylinder adapted for reciprocal movement in the axial direction of said cylinder, said piston being normally biased in one direction under the force of a bias spring said piston incorporating a rack extending in the axial direction of said cylinder, a pinion shaft rotatably supported by said cylinder and extending perpendicular to the axis of said cylinder with at least one end of said pinion shaft extending outwardly beyond the wall of said cylinder, the portion of said pinion shaft located within said cylinder incorporating a pinion in mesh with said piston rack, a high-pressure space defined by one of said cylinder caps and the front face of said piston in which high pressure space fluid pressure is increased when a door is closed, a low pressure space in which is disposed said bias spring, a communication passage extending from said front surface of said piston to the rear surface thereof in the axial direction of said Scylinder and speed control means comprising a check valve comprising a A4 F/1537h -4valve seat in the form of a reduced diameter portion of said passageway and a spherical valve closure body adapted to close said valve seat, and a release pin extending into said cylinder axially thereof from said cylinder cap defining one end of said high-pressure space and adapted to enter the front face of said piston, the arrangement being such that during the end portion of the closing movement of a door to which said door closer is affixed, said release pin moves said valve body off said valve seat, opening said check valve and allowing the working fluid in the high-pressure space to flow to said low-pressure space, thereby suppressing the damping action of said door closure whilst latching action of said door is effected.

In the case of the speed controller in the above-described construction, when a door is opened, the piston is forced to move in the direction in which the bias spring within the cylinder is compressed and the working oil flows from the low-pressure space to the high-pressure space through the communication passage so that the valve body of the check valve is moved away from its seat. As a result, the check valve is opened so that the flow of the working oil into the high-pressure space is not prevented. In this respect, the present LF/1537h LF/1537h invention is substantially similar to the conventional door closer in which a check valve is disposed in a piston.

When one let go hold of a knob or a handle of a door after he/she has passed through a door entrance, the external force exerted to the piston disappears so that the piston is forced to move toward the cylinder cap on the side of the high-pressure space under the restoring force of the bias spring which is disposed within the cylinder and has been compressed. In response to the displacement of the piston, the working oil tends to flow through the communication passage from the high-pressure space to the low-pressure space, but the flow of the working oil causes the valve body to seat on its valve seat to close one end of the communication passage opened at the valve seat, whereby the check valve is closed.

When the piston is displaced further after the check valve has been closed, the working oil in the high-pressure space which is increased in pressure by the displacement of S.,0 the piston flows through an oil passage into the low-pressure space. In this case, when the working oil flows through a small-diameter orifice, the viscous resistance is produced and consequently the movement of the piston and hence the door is damped. In this respect, the present invention is also substantially similar to the conventional door closer.

C CWhen the piston is further displaced to approach the end of the stroke of the piston, the leading end of the release pin extended from the cylinder cap on the side of the ,4t0 high-pressure space inwardly and axially of the cylinder interferes with the valve body of the check valve. When the piston is further displaced, because of the relative movement between the release pin and the valve body, the latter is forced to move away from the valve seat so that the check valve is opened. Then the working oil in the high-pressure space directly flows into the low-pressure space through the L i -I d il-- i' l'll' -C H6 communication passage which exhibits a low degree of resisti ance to the working oil. As a result, the damping action due to the above-described viscous resistance disappears so that i the latching action for quickly moving the piston and hence the door is produced.

3 When the position of the release pin in the axial direction of the cylinder is adjusted, the timing when the i leading end of the release pin starts to interfere with the S 10 valve body of the check valve is varied so that the latching action actuating time is also varied. More particularly, when the length of the release pin extended inwardly of the cylinder is longer, the latching action actuating time becomes faster, but when the length of the inwardly extended release pin is shorter, the latching action actuating time is delayed.

BRIEF DESCRIPTION OF THE DRAWINGS: 1% II S* Fig. 1 is a sectional view of a door closer incorpo- 70 rating a speed controller in accordance with the present in- 0 ,t vention and illustrating the door closing mode; Fig. 2 is a sectional view, on an enlarged scale, of a preferred embodiment of the present invention; and Fig. 3 is a sectional view similar to Fig. 1 but illustrating that a check valve is opened and the door closing I il operation by the door closer is completed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT: Now a preferred embodiment of the present invention I will be described in detail with reference to the accompanying drawings.

Referring first to Fig. 1, one end of a cylinder 1 is closed liquid-tightly with a high-pressure-side cylinder I- 1 I r- 7 cap 2 while the other end thereof is also liquid-tightly closed with a low-pressure-side cap (not shown) and the cylinder 1 is filled with a working oil.

A piston 3 is fitted into the cylinder 1 reciprocably in the axial direction thereof (in the right and left directions in Fig.1) and is biased in one direction (in the left direction ir Fig.l) under the force of a closer spring 4 (See also Fig.3). The piston 3 is further formed with a rack 5 extended in the axial direction of the cylinder 1.

In the vicinity of the mid-point between the ends of the cylinder 1, a pinion axis 6 is rotatably supported in the direction perpendicular to the axis of the cylinder 1 and at least one end of the pinion axis 6 is extended outwardly beyond the wall of the cylinder 1. A portion of the pinion O axis 6 extended inside the cylinder forms a pinion 7 which in 0 turn is in mesh with the rack o n3,0 When the piston 3 is forced to move to the left in o Fig.1 under the force of the closer spring 4 when the door is Q o closed, the working oil in a high-pressure space 8 defined between the front end (the left end in Fig.1) of the piston 3 and the high-pressure-side cap 2 is compressed and is forced to flow through an oil passage (not shown) and an orifice (not shown) into a low-pressure space. As the result, the 4 i movement of the piston 3 is damped and the rotation of the pinion shaft 6 in mesh with the piston 3 actuates a linkage consisting of the above-mentioned main arm and the fork arm so that the door is closed in a manner substantially similar to that of the conventional door closer. The construction and the mode of operation of the above-described door closer are well known to those skilled in the art so that no detailed description shall be made in this specification.

Meanwhile, as shown in Figs.1 and 2, a communication

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-8passage 9 is extended through the piston 3 in the axial direction thereof and one end of the communication passage 9 on the side of the high-pressure space 8 is terminated into a Svalve seat 11 (See Fig.2) defined by the circular edge of the opened end of the communication passage in the vicinity of the front end surface of the piston 3. A check valve 13 having r a ball-shaped valve body 12 is seated at the valve seat 11 thus defined. Referring still Fig.1l, a pin 14 is provided in order to prevent the valve body 12 from falling and a ball 16 is forced to be inserted into a filter housing hole in order to prevent a filter 15 from being pulled out.

A release pin 17 is extended inwardly from the highpressure-side cap 2 in opposing relationship with the check valve 13 in such a way that the release pin 17 partially makes interference with the locus of the displacement of the valve body 12 of the check valve 13.

In this embodiment, as best shown in Fig.2, the o release pin 17 comprises a small-diameter conical leading portion 17a, an externally threaded portion 17b, an O-ring receiving groove 17c and a screw slot portion 17d with a screw 41; slot formed at the outward surface thereof all of which are integrally formed in the order named from the inward to the y 25 outward. A stepped hole consisting of a large-diameter portion i and a small-diameter portion which is internally threaded is extended through the cylinder cap 2 in the coaxial direction t thereof. The externally threaded portion 17b of the release pin 17 is threadably engaged with the internally threaded o0 small-diameter portion of the stepped hole while the O-ring receiving groove 17c into which is fitted an O-ring 18 is fitted into the large-diameter portion of the stepped hole.

Therefore, the O-ring 18 can maintain the liquid-tightness of the cylinder 1 and when the screw slot 17d is rotated by a screwdriver or the like, the position of the leading end of the release pin 17 in the axial direction of the cylinder 1

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9 can be freely adjusted.

In the case of the embodiment with the abovedescribed construction, when the door is closed so that the piston 3 is displaced, the valve body 12 is forced to seat on the valve seat 11 under the pressure of the working oil, thereby closing the check valve 13 as shown in Fig.l, but as best shown in Fig.2, the conical surface at the leading end of the release pin 17 is made into sliding contact with the valve body 12 so that because of the sliding contact between them and the relative movement there between the valve body 12 is forced to move away from the valve seat 11 in the radial direction of the cylinder 1. When the valve body 12 is moved away from its valve seat 11 once, the flow of the working oil from the opening at the valve seat 11 toward the low-pressure space further forces the valve body 12 away from the valve seat 11 so that, as best shown in Fig.3, the valve body 13 falls into a pocket defined between the valve seat 11 and the pin 14 for preventing the valve body 12 from roll- 1,20 ing out of the piston 3.

~As is apparent from the above description, according to the present invention, almost at the end of the door closing stroke by the door closer, the check valve is opened by utilizing the interference between the leading end of the release pin and the valve body of the check valve so that the damping action of the door closer is suppressed while the latching action is produced. Furthermore, the position of the release pin in the axial direction of the cylinder can be adijusted, the present invention can attain the effect that the adjustment of the door closer actuating time becomes remarkably simple.

Claims (4)

1. A door closer comprising a cylinder filled with a working fluid and whose both ends are closed in liquid-tight manner by cylinder caps, a piston within said cylinder adapted for reciprocal movement in the axial direction of said cylinder, said piston being normally biased in one direction under the force of a bias spring said piston incorporating a rack extending in the axial direction of said cylinder, a pinion shaft rotatably supported by said cylinder and extending perpendicular to the axis of said cylinder with at least one end of said pinion shaft extending outwardly beyond the wall of said cylinder, the portion of said pinion shaft located within said cylinder incorporating a pinion in mesh with said piston rack, a high-pressure space defined by one of said cylinder caps and the front face of said piston in which high pressure space fluid press.re is increased when a door is closed, a low pressure space in which is disposed said bias spring, a communication passage extending from said front surface of said piston to the rear surface thereof in the axial direction of said cylinder and speed control means comprising a check valve comprising a valve seat in the form of a reduced diameter portion of said passageway and a spherical valve closure body adapted to close said valve seat, and a release pin extending into said cylinder axially thereof from said cylinder cap defining one end of said high-pressure space and adapted to enter the front face of said piston, the arrangement being such that during the end portion of the closing movement of a door to which said door closer is affixed, said release pin moves said valve body off said valve seat, opening said check valve and allowing the working fluid in the high-pressure space to flow to said low-pressure space, thereby suppressing the damping action of said door closure whilst latching action of said door is effected.

2. A door closer as defined in claim 1 further comprising a valve Sbody movement limitation pin located within said piston radially of said cylinder and extending into the portion of said communication passageway between said valve seat and said piston front face.

3. A door closer as defined in claim 1 or claim 2 further comprising a fluid filter located in said communication passageway between said valve seat and said low-pressure space and a ball adapted to retain said filter in its predetermined location. RLF/1537h jj 1 -11-

4. A door closer substantially as described herein with reference to the accompanying drawings. DATED this TWENTY-THIRD day of DECEMBER 1991 Miwa Lock Kabushiki Kaisha Patent Attorneys for the Applicant SPRUSON FERGUSON a a3 a u ao ato S a a RLF/1537h